CN101558174B - Method of metal performance improvement and protection against degradation and suppression thereof by ultrasonic impact - Google Patents

Abstract

A method of improving and strengthening the performance of metal and protecting the metal against degradation and suppression thereof by controlling ultrasonic impact is disclosed. The method addresses the problems of degradation of metal properties during prolonged service under external forces, thermodynamic fluctuations and negative environmental factors. The method also relates to the technologies oriented to protect against (prevent) and to suppress the danger of materials failure due to unfavorable change in performance over time. The well-known methods of 'combating' metal degradation cover a wide range of technologies from metallurgical alloying during melting, casting, welding and application of coatings to various thermal treatments and effects on the surface. The invention provides a new versatile method of addressing degradation problems in all these cases.

Description

Improve metallicity and prevent and suppress deteriorated method by ultrasonic impact

Invention field

The present invention relates to improve metallicity and prevent method and the algorithm (algorithm) that metal is deteriorated and inhibition is deteriorated by ultrasonic impact.The present invention puts forth effort to solve the deteriorated problem of the metallicity in the life-time service process under external force, thermodynamic fluctuations and Negative Environment's.The present invention opposing namely prevents, and suppresses the danger of the material failure that unfavorable variation that do as one likes can occur in time causes.These problems are usually destroyed by the primary formation of material/metal under the known conditions of the environment deterioration process that is accompanied by metal and are caused.

Background of invention

United States Patent(USP) Nos. 6,171,415,6,289,736,6,458,225,6,338,765,6,722,175 and 6,843,957 and U.S. serial No.10/834, the 180th, well known in the prior art, they disclose the direct acting ways and means of ultrasonic impact processing to material situation and performance, mean the surface of material and the integral entity that next top layer is this effect and result.

Deteriorated all kinds (classification), cause, physical properties and mechanism are known.For example, Degradation of Mechanical SystemsBerman A.F. work (Novosibirsk:Nauka, 1998,320 pages of-Di) be as known in the art, it discloses material degradation process, the component failure in the structure and has been subjected to research and the formal result of the structure organization of the unique mechanical system fault that the comprehensive action of factor affects.The material damage and the component failure process that are caused by corrosion cracking, hydrogen embrittlement, corrosion and mechanical fatigue and erosion have also been described.

The result of experimental study, test and the service experience of mechanical system (MS) is solution and the Information base of keeping, maintain and recover relevant problem of the reliability of MS and the technological system (TS) that is made of mechanical system and security.The reliability that this work is puted forth effort to solve by the deteriorated MS that causes changes.Deteriorated irreversible change process, malfunction and the dangerous operation that refers to technical qualification of MS.The deteriorated of MS is to need the fault of change structure portative power and the part of unexpected accumulation.

In order to provide reliability in the manufacturing stage; based on the understanding to possible deterioration process; make great efforts exploitation and improve schema and model; set up diagnostic element and the standard of inefficacy and ultimate limit state, and the technology of confirmatory test method, definite diagnosis and forecasting techniques condition and guard method is to prevent the expansion of emergency situation and accident.

In order to ensure reliable and safe operation, to the understanding of deterioration process can effectively control and assess cause, the updating component of the technical qualification of MS and variation thereof life-span and diagnosis frequency, improve diagnosis and forecasting techniques and renewal MS.

Mechanical system consists of the almost architecture basics of any technological system.Therefore, intensity and the life-span of bearing structure and mechanism are most important in the general method of reliability consideration and maintenance.

The fault of MS and the life consumption of parts characterize with fault and ultimate limit state standard.Processing safety and necessary life-span diagnosis and the forecasting techniques by maintenance, the diffusion of compensation external action and the randomness thereof of work capacity and portative power realizes.

In the past recent decades, more studied the inefficacy cause in power engineering, chemistry and petrochemical industry and the transportation in great detail.This is verified causes the life consumption (deteriorated) of MS and phenomenon and causal complicacy and the diversity that lost efficacy.For example, studies show that of the inefficacy in the chemical reactor, since the Disadvantageous combination of machinery, physics and chemistry effect, the saturating wall crack propagation in the heat exchanging pipe.This may be because incomplete standard and rule, manufacturing and inspection technology and operational condition, with and break rules.Therefore, intensity and the life problems of MS and parts thereof solve far away, and especially owing to external factor and small-scale MS and the TS of uniqueness, its inefficacy causes significant economy and societal consequence.

A kind of mode of head it off is that material and method of structural mechanics are combined with the theory of stochastic process.This is the basis of MS reliability theory.The possibility of deterioration failure suitable maintenance system and Life Design quite little and physical properties by taking into account deterioration failure in the life-span boundary that dopes realize.Only based on the research of the machinery-physical-chemical property that lost efficacy, namely in the situation of the mass space of (but operational condition) that the mechanism that is fit to the designing a model of inefficacy character, deterioration process and dynamic (dynamical) model and MS as a whole and each parts thereof can be provided, just can make the effectively computable in life-span.

But, the operating experience of unique chemical process system shows, inefficacy above 30% designs a model owing to the imperfection under the effect in machinery-physical-chemical factor really, it can not realize reliable life prediction, but produces the design solution of technical qualification and the recoverability that can not assess MS.

Inefficacy in this case be to a great extent because laboratory condition (comprehensive action of high pressure and high temperature, active and rodent environment comprises fast-changing environment; The low rate that can not accelerate of many deterioration processes, etc.) non-repeated of lower external factor causes and can not carry out sufficient experimental study.Undoubtedly, not enough experimental study and test and therefore lost efficacy and the shortage of effective standard of ultimate limit state causes unsuitable maintenance.

The parametric reliability theory comprises the physical mechanical failure model based on the computed reliability parameter.This theory points out that the output parameter of product is owing to wearing and tearing and the damage of each parts change.But in many cases, output parameter stops or insensitive to the destruction value before the criticality of moment during breach of security operational condition in function.For example, at the function termination, since saturating wall cracking or fragility or ductile fracture, cracking in container, pipeline and other parts.

In this case, regulation characterizes the parameter (crack depth or length etc.) of the danger of through crack formation or hydrogen embrittlement.Under the diagnostic utility of electric current controllability and many MS, this class parameter usually exceeds control or control is not enough.Therefore, should by may with the analysis of destruction of supposition and the reliability that probability assessment is kept this class MS.Acquired results is being controlled the measure that prevents from losing efficacy and enlarge and security is provided.

The fault of MS is one or several component failures terminal stage before, and it is again to be caused by the damaged material that reaches threshold value.According to material character and external factor, adopt various parameters as impaired criterion.The variation of the variation of the physics of damage parameter exosyndrome material, chemistry and mechanical properties and surface and structural condition.

Basically, present measuring technology is because its topical application or because this industry lacks necessary technique means and can not detect the initial destroy stage, this should consider in the MS performance history.This brings the problem of the diagnostic device of determining that direct and indirect diagnostic element and the situation in exploitation evaluation and test and prediction experiment and the use procedure are required.

It is substantially nonlinear being described in the relation that changes the process of material character and state under the various factors comprehensive action.Mainly study by rule of thumb these processes and make its formalization.Also there is the dynamic (dynamical) evaluation and test of material damage under the various combinations with external factor and predicts relevant problem.

To the multiple-effect of MS and TS, especially in chemistry, petroleum chemistry, nuclear engineering, physiotechnology and pipeline foundation facility, cause diversified deterioration process, they cause complexity destruction, life consumption and the MS fault of material.Identifying possible deterioration process is the front research of design and the most important target in the design effort.

Carry out a large amount of physics of metals, metallurgy, physical chemistry, intensity, weather resistance and other research and test to study these processes.The main purpose of this class research is to determine mechanism, kinetics and the dynamics of structure and change of properties according to initial parameter.The monograph that G.P.Karzov edits is intended to various research methods up-to-date of the failure procedure that occurs in compound material and the structure and one of the most comprehensive achievement.

In many cases, be widely used and the fully reliability method of research, for example be not suitable for can not based on intensity and life standard provides structural redundance or the MS of correct assessment reliability.For example, the main failure criteria of pipeline, tubular type equipment and pressurized vessel is by the seal failure that saturating wall destroys or component failure causes, leaks or the atmosphere infiltration thereby cause.

Any destructive process can be described with its mechanism, kinetics and dynamics.The mechanism of destructive process refers to determine combination and the interaction of the factor of this process; Kinetics refers to the destruction such as microcosmic and/or Macro-event that occurs owing to the merging of elementary motion event or accumulation; Dynamics refers to this process velocity variations in time.Therefore, failure mechanism (degradation mechanism) is relevant with the many factors that affect component materials; Kinetics is relevant with material timely response to given effect in microvolume and submicroscopic volume with dynamics; The consequence of the external effect in damage parameter and the piece volumes is relevant.Each destructive process all is an aggregation process, and it is accompanied by effect and special causal compound action.Any destructive process all has the principal element of minimum number, and they are regarded as the basis with this process classification usually.

Character and the origin cause of formation that identification MS component materials lost efficacy are basic, because this formation: assessment intensity and the basis that designs a model in life-span; The standard of selecting properly test method and condition; The diagnosis of checking MS, the initial information of predicting and improving one's methods.

Aspect the weather resistance and reliability of MS, should study failure mechanism, kinetics and parameter and come reasonably alternative pack or structured material in order to not only consider manufacturing technology, also main the setting lost efficacy and standard, periodicity and the control of ultimate limit state and the Forecasting Methodology of diagnostic means, technical qualification, reliability and security.Physics of metals scholar and metallurgist use term " material failure ", and intensity and reliability expert use " component materials destruction " or only use " parts destruction ".

The chemically reactive of material improves under stress, and this raising is under pulsating stress even larger.Therefore, intensity and life search should not only limit to machinery standard.Cause the corrosion-physical disturbance of MS component failure mainly the equipment failure in chemistry, petroleum chemistry, oily processing unit (plant), electric device and gas and the oil-piping to be responsible for.This equipment is designed to the transportation of the important medium of thermal mass transmittance process and chemistry, oil and power technology.

Material damage be described to by various destruction micromechanisms, the heat fluctuation of time with on nuclear, dislocation, substructure and structural level in the statistical relationship of the phenomenon multistage statistics and the large scale process that cause.Use pure machinery standard to be evaluated at intensity under load and the medium comprehensive action and life-span and can not guarantee that accuracy can not improve these standards and affect destructive process.

Result based on experimental study, test and controlled work, some modal component materials destructive processs of almost not understanding have been solved, such as the physical mechanical essence of corrosion cracking (CC), hydrogen embrittlement (HE), corrosion fatigue (CF), mechanical fatigue (MF) etc.Detection is to one or responsible greatest factor and the definite damage parameter of describing each process of other deterioration process.Table 1 has shown the classification of principal element, and it comprises various failure mechanisms and specifies destructive process and parameter.The destructive process that is caused by principal element can be realized under the various quantitative relations between the additional factor of the various piece of factor, each factor and initiation and this process of acceleration.

The classification of significant parameter, mechanism and the process of table 1-material damage

Table 2 has shown the classification results that is had the common and the most dangerous type of remarkably influenced and the damage parameter take cracking as feature the MS life-span.

Table 2-cracking parameter is strengthened

Be known that equally Accelerated Aging of Materials and Structures:The Effects of Long-Term Elevated-Temperature Exposure (adding of material and structure Speed is aging: the impact that long term high temperature exposes)(National Materials Advisory Board of USA (NMAB), 1996), it is for the problem of the test procedure of used various materials in aircraft industry of developing life-span that can their deteriorated and new aircraft components in use of reliable prediction.In order to predict the response of material system long-term exposure in the airframe environment for use, must develop and destroy and the basic comprehension of the relevant physical phenomenon that lost efficacy.This by experiment the sign of material set up with relevant mathematics and exploitation computation model of describing physical phenomenon.In many cases, testing standard and coding can be used for instructing the particular type of part design and test method.But for some advanced materials, for example mixture may need different testing of materials methods, and may lack standardized method.Although the requirement to identical basic material character may be similar, the user develops themselves test method usually.Different testing method may cause the uncertainty of testing data, causes the uncertainty of material selection, Design and manufacture.

Use the Long-term Aging response of accelerated test and analytical procedure evaluation and test material and structure very difficult, the complicated state that runs in especially using for flyer.Even best-of-breed technology also may not can produce the prediction that is entirely satisfactory of material property.But owing to will design new flyer and evaluate and test material and structure in its whole life cycle, developing test and the analytical procedure that can understand as far as possible best material and structure properties is important for support material selection and structure design decision-making.In time provide the fragmentary data that affects the key procedure decision-making better than the fully strict data that await development out.

Consideration to these problems causes US National Aeronautics and Space Administration (NASA) to require National Research Council ' s National Materials Advisory Board (NMAB) to identify evaluating method and following flyer material and the weather resistance of structure within its whole work-ing life of analytical procedure sign of the problem relevant with the timeliness of advanced material and proposal use acceleration.Set up NMAB research committee and provide the summary of long-term exposure on the impact of following high performance aircraft structure and material with (1); (2) recommend to the improvement of analytical procedure and make lab investigation and method that analytical technology is accelerated with characterize and the prediction material to the response of possible flyer Working environment; (3) determine to develop and verify required test, anticipate ability and the required research of evaluating standard.

The general degradation mechanism that must consider, namely the physical event under viewed deteriorating effect or event chain comprise:

The variation of-microstructure change and composition,

The deformation of-time-dependent manner and the destruction accumulation that causes,

The acceleration effect of the temperature of the invasion and attack of-environment and rising, and

The synergistic effect of-above-mentioned situation.

In the past, the main failure mechanism of aluminium alloy was corrosion and fatigue during flyer was used---the common mechanism relevant with an aging group of planes.Latent destruction mechanism comprises microstructure change, fatigue, creep and environmental effect.

The mensuration of most critical degradation mechanism depends on which character is important in specific end use.For example, if intensity is crucial, the alligatoring of matrix throw out in the applied at elevated temperature process is important; If toughness is crucial, the expansion in grain boundary precipitate or sediment-free zone is important; If creep or fatigue are crucial, the forming core of tiny crack, growth and joint are important.Use relevant Latent destruction mechanism with the high temperature of aluminium alloy and comprise microstructure change, fatigue, creep and environmental effect.

High temperature exposure under applied stress can cause many microstructure change, comprises the expansion (being important in the application of toughness key) in the sedimentary alligatoring of matrix (being important in the application of intensity key) and grain boundary precipitate or sediment-free zone.The forming core of space or tiny crack, growth and joint have reduced fatigue resistance.Anti-high cycle fatigue is responsive to the tiny crack forming core at the inhomogeneous place of microtexture, and the impact that the fatigue crack growth threshold is subjected to the unrelieved stress degree and is shielded by the crack-tip that the variation in the microstructure produces.As if creep resistance improve with the raising of granularity.In addition, cold-working has already reduced the creep resistance in the aluminium alloy that precipitation strengthens and dispersion strengthens.For aluminium alloy, the degradation mechanism that is caused by the environment for use interaction that needs to consider comprises burn into stress corrosion crack, hydrogen embrittlement, solid-METAL EMBRITTLEMENT and liquid-METAL EMBRITTLEMENT.

Three associated problem relevant with the possibility of the complicacy of breaking-down process in the titanium alloy and Time-temperature-hydrogen dependency failure mode may hinder for the high strength of High Speed Civil transportation (HSCT) purposes and the exploitation of high-tenacity titanium alloy.These problems comprise that microstructure change is on the impact of deformation and local fracture, uncertainty and the hydrogen embrittlement of moderate temperature deformation behavior.

Using three principal elements that need to consider at the long term high temperature of the high strength that is used for the HSCT purposes and high-tenacity titanium alloy comprises:

-similar with situation about aluminium alloy having been developed, the impact that should research and develop microstructure change (for example β granularity, α volume fraction, grain boundary α form, the α form during timeliness and the variation of metastable phase),

-moderate use temperature and the impact of loading rate alloy performance, the possibility, thermal activation that comprises dynamic strain aging are slided localization, Time-temperature to impact and the deformation under cryogenic temperature and the fracture behaviour of hydrogen embrittlement, and

-because from erosion environment condition, the dissolved oxygen of airplane hydraulic pressure fluid for example, stretching ductility and fracture toughness property deteriorated.

Be known that equally High Temperature Degradation in Power Plants and Refineries (high temperature in power house and the refinery is deteriorated), (Mat.Res. rolls up 7, no.1. for Heloisa Cunha Furtado and Iain Le May work Carlos.2004 January/March), it discloses high temperature degradation mechanism and this class and has destroyed appraisal procedure with the residue safety operation life-span.Main degradation mechanism in the high temperature service is that creep fracture, microstructure are deteriorated, high temperature fatigue, creep fatigue, embrittlement, carbonization, hydrogen destruction, greying, thermal shocking, erosion, Liquid Metal Embrittlement and various types of high temperature corrosion.In addition, stress corrosion crack and aqueous corrosion may consist of problem, although usually do not expect these failure mechanisms in high-temperature component.But when parts cool down and liquid still is present in wherein or is in contact with it, they may occur.Consider again each side separately.

Creep is one of the most serious high temperature failure mechanism.Creep relates to time-dependent manner deformation.The high temperature creep cracking develops in the intergranular mode in the parts with engineering importance (it is through inefficacy after long-time and comprise boiler superheater and other parts, petroleum chemistry stove and reactor parts and the gas-turbine blade of at high temperature operation) usually.Under comparatively high temps, as contingent in the situation of local superheating, deformation may localize, and is accompanied by large plastix strain and partial wall attenuation.In lower slightly temperature with under corresponding higher stress level, fracture may be transcrystalline in nature.

Microstructure is deteriorated to be possible pass through some other processes, and for example creep, fatigue or other rapidly fracture cause the failure mechanism that lost efficacy.Microstructure is deteriorated to be a kind of failure mechanism, because it may cause the remarkable loss of the strength of materials.

The fatigue relevant with stress application repeatedly at high temperature can cause inefficacy at low temperatures as it.At high temperature in the parts of operation, fatigue produces by temperature variation usually, and this temperature variation can cause cyclic thermal stres, and this can cause thermal fatigue cracking.In the expansion of high constraint, detailed mechanism may be a kind of Local creep deformation to this cracking easily.

Creep-fatigue interacts and to relate to the complicated destructive process of creep strain and pulsating stress, and main failure mode can be from the main fatigue crack growth under upper frequency and lesser temps to main creep fracture (wherein long and temperature of hold-time be in this level other is high-end).

The embrittlement that precipitation causes can occur in many different modes.For example, keep at high temperature or the formation that cycles through δ phase in the austenitic stainless steel of critical temperature range (about 565 to 980 ℃) causes loss in ductility and embrittlement.Ferritic stainless steel may stand the embrittlement phenomenon when remaining on or being cooled to 550 to 400 ℃ temperature range.If temperature condition is considered to cause this class effect, after the long-time exposure before the Fracture propagation outside expecting, the metallography inspection is desirable.Except the embrittlement that in use exposes ferritic steel at high temperature with by the δ embrittlement that forms the austenitic stainless steel that causes mutually, when parts at high temperature were exposed in the carburizing atmosphere for a long time, the carbonization meeting produced hard brittle material.

The special hydrogen that occurs in petroleum chemical plant destroys and may occur owing to atomic hydrogen is diffused in the metal in carbon steel, at this atomic hydrogen and Fe ₃Carbon among the C is in conjunction with forming methane and eliminating the perlite composition.This is the deteriorated Special Circumstances of microstructure, and owing to use the low alloy steel contain the element that makes the carbide stabilization, this situation nowadays with compare in the past much rare.

In ferritic steel, after long-time exposure at high temperature, because the cementite in the perlite is reversed into more stable graphite-phase, greying may occur.This is the deteriorated a kind of particular form of microstructure of in the past relatively often observing in the petroleum chemistry parts.Along with developing more stable CrMo steel, this situation is nowadays uncommon, but (wherein temperature height and material imperfect stability) can occur frequently in petroleum chemical plant and in vapour generator.

Thermal shocking relates to rapid temperature variation, and it produces precipitous thermograde and therefore produces heavily stressed.This load can crack, if particularly impact load is repeatedly.Consequent crackle is expanded by thermal fatigue course.Give birth to hot charging put with refinery under normal running (operation) conditions, can not run into this class situation, but may in emergency situation, occur or owing to the skew of operational conditions occurs.Hard brittle material to the thermal shocking sensitivity many, this class is destroyed responsive such as the ceramic component that in advanced gas turbine, becomes more common.

When having particle in the flowing gas, in high-temperature component, may corrode.This is common situations in burning the power station of coal, and wherein the erosion that causes of flying dust can cause the inefficacy in pipeline attenuation and economizer and the reheater, and the sootblower erosion can cause those ducted superheaters in the passage of gas blower and the attenuation in the reheater.The solution page that flying dust corrodes depends on that the improvement boiler smoke distributes and the local too high gas velocity of reduction.Many factors are depended in the control that sootblower corrodes, and comprise the too high maintenance that blows pressure, difference and effective pipe protection is provided when needed.

For the combination of many liquid state-solid metal, Liquid Metal Embrittlement (LME) may occur, for rendering industry have a serious consequence a kind of be the LME of the austenitic stainless steel that caused by zinc.Rapid embrittlement can occur being higher than under 750 ℃ the temperature, and have the Zn source according to observations, for example during the galvanized steel structure unit or when the pollution that exists from Zn base lacquer, produce widely cracking after firing in parts of stainless steel.Significant cracking (Flixborough, North Lincolnshire, England, 1974) is caused in a rear source when the Flixborough disaster.Cracking is (m/s) extremely rapidly, and the stress level that this class cracking is occured can be low to moderate 20MPa.

Be used for the alloy that high temperature uses corrosion minimize the formation of depending on the protective oxide layer.Perhaps, for the alloy that at high temperature has very high strength character, may not need to apply protective coating.Being generally used for providing the oxide compound of protective layer is Cr ₂O ₃And Al ₂O ₃Corrosion protection destroys by the mechanical failure of protective layer usually, and described mechanical failure relates to by thermal cycling or by the oxide compound spallation of corroding or impact causes.

Above-mentioned these are not usually the mechanism relevant with the hot operation parts.But when device was stopped work, fluid may condensation and may have the water that contains pollutent in the pipeline of this device or container.The corrosion that occurs at low temperatures or stress corrosion crack may cause the preferential destruction under the high temperature in the subsequently operational process of this device.

Be known that equally Interaction of Structural Defect and Degradation of Structural Material Properties (the mutual work that textural defect and structured material character are deteriorated With)G.A.Filippov and O.V.Livanova work (All-Russian Conference Structural Defects and Crystal Strength, Chernogolovka 2002), it discloses the deteriorated anti-brittle rupture that show as reduction of tube metal character after long-time the use, comprise brittle delay fracture, and caused by the strain aging of steel.The pipeline life-time service shows the timeliness mechanism of also endeavouring to solve pipe line steel to the impact of mechanical properties and splitting resistance.Tubing sample to 19 main pipelines moving under various weather condition is studied.The 17MnSi shaped steel up to 80% that consists of all pipelines is carried out basic statistical study.In order to evaluate and test mechanical properties, from operating pipeline, urgent capstan winch and emergency stock, extract sample.Useful life is 4 to 44 years.Adopt the metal that uses in the present production of Orsko-Khalilovsk Metallurgical Factory and from the pipeline of emergency stock as initial conditions.

Standard mechanical character, tensile strength for example, σ _{τ s}, yield strength, σ _YG, elongation, in fact δ and area reduce ψ can not become along with use (seeing Table 3).In catter limits, the experimental data (σ that is near the mark _{τ s}-520MPa at least; δ-at least 24%).In order to show the character to the structural changes sensitivity, need other test, comprise the test to rapid area of stress concentration sample and precrack sample; Also should evaluate and test crack nucleation and expansion.

When using sharp notch sample testing pipeline (seeing Table 3), find that shock strength reduces.After using 20-25, the KCV under+20 ℃ (shock strength) is worth (KCV ^{+ 20}) be down to 30-50J/cm from 55-70 ²Shock test in-40 to+20 ℃ temperature range shows that along with Service life, tube metal changes into the critical temperature (T of brittle state ₅₀) shift to comparatively high temps (seeing Fig. 1).After using 25-35, the cold short threshold value of temperature becomes and is higher than 0 temperature range.When pipeline reaches about 25 years usage period, characterize such reduce of all values shown in sharp notch statistics pliability test of tube metal strength at break.Viscous deformation reduces approximately, 1.5 times.After 25 year usage period, mainly due to cracking patten nucleus power A _nReduction, total energy-to-break A of tube metal _∑Reduce about 1 half (seeing Table 3).Crack expansion power A _pReducing than low degree.Therefore, the structural changes of tube metal in the life-time service process has maximum effect to cracking patten nucleus power.

Fig. 1 has shown the tube metal for steel 17MnSi, and the life-span is to brittle state (T ₅₀) impact (symbol refers to be higher than+20 ℃ of lower brittle state transformation situations) of transition temperature.

The critical crack open C OD that affects the ultimate deformation of crackle generation significantly reduces-about 1.5 times at 20-25 after the usage period.This means that the susceptibility that the steel counter stress is concentrated improves, namely at first is not that breakneck stress concentration (cut, scratch, indenture etc.) on pipe surface can be owing to the structural state in the tube metal becomes serious behind life-time service.

Therefore, in the life-time service process, tube metal stands the variation of structural state, and this causes the reduction of anti-brittle rupture.Can point out that this occurs owing to the raising of anti-microplasticity deformability and the higher local microstress under load.

The mechanical properties of table 3-17MnSi type pipe line steel in the life-time service process is deteriorated

The structural state variation of tube metal may be due to the defective accumulation that is caused by stress effect, corrosive atmosphere and hydrogen.Corrosion process changes the surface appearance of tube metal, makes the saturated hydrogen of metal, and this must form internal tiny crack shape defective.The accumulation of tiny crack shape defective and fracture is commonly referred to as delayed fracture under the static state of the final fracture stress that is lower than steel and yielding stress or quasistatic stress.Delayed fracture is the origin cause of formation that is exposed to the too early brittle rupture of the important high-duty steel part (such as tightening screw, strain steel wire etc.) in the corrosive environment.

Be exposed at the same time according to the program of special exploitation and carry out the delayed fracture test under stress, corrosive atmosphere and the hydrogen.Delayed fracture has three phases: the slow growth of latent period (crack nucleation stage), stationary crack and rapidly fracture.For assess pipeline may with condition that corrosive atmosphere contacts under reliable operation, most important assessment is to find out cracking resistance line forming core and extendability (is unlike in the Impact Test rapid like that, but slowly), shock strength that Here it is can not affect the reason of the cracking resistance line formative of pipeline.

Fig. 2 has shown the pipeline for steel 17MnSi, rupture time t _fWith initial stress specific strength K _iRelation: when 1-dispatches from the factory; The 2-service pipe; The 3-pipeline of meeting an urgent need.The long-time delayed fracture tendency that affects tube metal of using makes K _i-vs-t _fCurve is shifted to lower rupture time zone.Therefore, as shown in Figure 2, at identical K _iLower, the rupture time of the pipeline when dispatching from the factory is more much higher than service pipe and emergent pipeline.

Stable crack growth rate also depends on the life-span.The metal of the pipeline when dispatching from the factory has (1-3) * 10 ^-4The minimum stable crack growth rate of mm/min.The work-ing life of pipeline is longer, and steady crack growth speed is just higher, and this speed is near about 80 * 10 ^-4Mm/min.

In order to understand fully that why the anti-brittle rupture of tube metal reduces, and carries out strain aged test under the life-time service condition.In the life-time service process, the lower resistance to fracture of the serious condition of the structural state variable effect of tube metal (sharply area of stress concentration or low temperature), and this is obvious relevant with the strain aging process.Therefore, importantly, study this process in order to understand the mechanism that resistance to fracture changes.

Only when solid solution contains certain density carbon and nitrogen-atoms, just observe the strain aging of iron and soft steel.Strain aging causes improved tensile strength, yield strength, hardness; Surrender steady section on the SN curve; The critical embrittlement temperature that in shock test, improves; Lower plasticity.Strain aging trend is the critical nature of metal.

In order to assess above-mentioned metalline, sample stands to surrender the tension force under the component (2%), descends maintenance 1 hour and tests tension force at 200 ℃.Increase the trend of finding strain aging, Δ σ by the yield strength after stopping in active deformation _s(Δ σ _s=σ _s-σ _2%).Δ σ _sHigher, the trend of strain aging is larger.In addition, the area by tube metal under the aged reduces ψ _sEvaluate and test plasticity.

As seen from Figure 3, in the life-time service process, the strain aging trend of steel reduces, i.e. the growth Δ σ of yield strength _sReduce less with the area under aged.This is the strongest between the usage period at initial 15-30.Use is to strain ageing trend Δ σ _sImpact be presented among Fig. 3 and the area of timeliness pipeline reduces ψ _sBe presented among Fig. 4.

Common understanding is that the strain aging trend of iron and steel depends on free state in the sosoloid, the impurity of namely not being combined with dislocation (carbon and nitrogen) content.In order to study the timeliness mechanism of tube metal under the life-time service condition, use the internal friction method of masurement of the localized variation in the steel construction situation to sensitivity.

Measuring result by internal friction temperature dependency (IFTD) is judged carbon and nitrogen content in the sosoloid.Be well known that the IFTD curve that contains the steel of uncombined carbon and nitrogen has by the kinetic about 40 ℃ Snoek maximum value of free clearance atom in stress field.Free carbon and nitrogen-atoms are more in the sosoloid, and the Snoek maximum value is larger.

The IFTD curve of the sample that from the pipeline after 30 years long-term uses, downcuts as shown in Fig. 5 and 6, have 60 and 200-200 ℃ under two maximum values.The internal friction temperature dependency of the tube metal of 17MnSi steel after long-term use in 30 years, Q-1 is presented among Fig. 5, being presented among Fig. 6 in emergency stock.In the situation of the IFTD curve of the sample that downcuts from urgent reserve tube road, the maximum value under 60 ℃ is higher.In the IFTD curve, the known interstitial impurity content of working as is higher than 2-10 ^-4Observe the Snoek maximum value during %.Therefore, can infer, use carbon in the pipeline sosoloid in 30 years and nitrogen content near 2 * 10 ^-4%, namely under the pipeline condition, the carbon in the free sosoloid and nitrogen content are tending towards reducing.Under the pipeline condition, owing to plastic deformation reduces, this causes new dislocation to be fixed by carbon and nitrogen-atoms in the pipeline use procedure for carbon and nitrogen content, forms the what is called " atmosphere " of impurity atoms and reduces its mobility in dislocation.Also demonstrate the trend that produces strain ageing under the pipeline condition in the peaked raising under 200-250 ℃ in the IFTD curve, this raising only just can be observed when metal bears plastic deformation and timeliness subsequently.

Therefore, in use, pipeline withstanding pressure and temperature head and dynamic and static load.The pipeline working conditions makes in the metal strain ageing may occur, causes local stress " peak " danger that improves in the anti-dislocation motion of raising and the metal.Therefore, the local stress in recess or the crackle summit is lax to be reduced, and has improved the brittle rupture trend of steel.Dangerous for the brittle rupture that reduces the pipeline that use to surpass 20 years, especially in the winter time under the low temperature, after pipeline is stopped work, in pumping plant activation process, should consider the cold shortness of the raising of the tube metal that caused by strain ageing.

Correspondingly, draw following results:

1. in order to assess the situation of main pipe line, the knowledge of traditional mechanical properties is not enough.The reliability assessment standard should comprise the character to the local structure sensitive, for example by delayed fracture test and at low temperatures the test of the sample of cracking or sharp notch is obtained those.

2. after the sample after using 25 years carried out the sharp notch pliability test, all resistance to fracture of metal reduced.Under the effect, the delayed fracture trend of steel it is found that structural changes especially responsive in stress, corrosive atmosphere and hydrogen.

3. in the life-time service process, tube metal character is because strain ageing and variation, and its mechanism is that the concentration of uncombined carbon and nitrogen-atoms reduces and the reduction of dislocation migration rate.

Be known that equally Environmental Degradation of Metals (Corrosion Technology) (environment of metal deteriorated (corrosion technology)), U.K.Chatterjee, S.K.Bose, S.K.Roy work (Marcel Dekker, 2001), it discloses all types of environment that metal component may stand in its processing, storage and use procedure deteriorated.Scope comprises basis, form and the prevention such as the types of degradation of aqueous corrosion, rust dirt and fouling process, alloy oxidation, liquid-metal corrosion, hydrogen attack and radiation injury.

In order to understand fully general and local corrosion effect, the effect of atmospheric exposure, high-temperature gas, soil, water, weak and extensive chemical product, liquid metal and nuclear radiation is disclosed.This disclosing shows also how the improvement of part design can reduce corrosion; Oxygenant, for example oxygen, sulphur and water vapor, halogen and CO ₂High temperature and the details of cryogenic effect; Instantaneous and the delay of having studied the solid metal that contacts with liquid metal was lost efficacy; Emphasized the impact of hydrogen on metal, comprised that loss in ductility and inside are peeled off, foaming, crack and cracking; Summarized the radiation effect to metal, for example radiation growth, space swelling and embrittlement and Geng Duo.

In addition, the disclosure comprises following major topic: type and prevention (the thermodynamics aspect of metal-oxide agent system of aqueous corrosion, rust dirt and fouling process; Kinetics aspect and rate process; The defect chemistry of oxide compound and other mineral compound; The mechanism of rust dirt and fouling process; Grown by the scale that lattice and crystal boundary diffusion cause; In oxide skin and the formation of space, hole and other large defective in substrate; Stress and strain expansion in the scale in growth; Dissolving and the diffusion of oxygenant in metal; Prepare and pretreated defective the metallic surface), alloy oxidation, liquid metal adheres to and hydrogen attack.

Be known that equally Accelerated Degradation (accelerated deterioration), Brigitte Battat work (NY 2001 for AMPTIAC, Rome), it discloses the summary of material degradation and accelerated deterioration method.The test of being undertaken by accelerated deterioration or timeliness measure product character in time under the unfair stress condition.

Material timeliness or deteriorated sign are owing to can not simulate in vitro environment for use but difficulty.Cyclic loading or repeated load, temperature, radiation, humidity and other effect that affects environment interact and can not reappear, especially in the situation of flyer operation.Yet therefore new part design can and be necessary for new design and produces testing method and analysis based on the material of having evaluated and tested in whole life cycle and structure.

Table 4 is (based on collecting (referring to Nelson about the data of the books of accelerated test from Nelson, W., Accelerated Testing:Statistical Models, Test Plans and Data Analyses, Wiley Series in Probability and Mathematical Statistics, 1990, the 11-49 pages or leaves)) classification of degradation mechanism, material that they affect, used acceleration stress factors and weigh the tested character of this response are provided.For example, fatigue occurs in metal, plastics etc., and the acceleration stress factors can be temperature, load or chemical reaction.Tested character is residual life and cumulative damage effect.This information helps to produce the model that can extrapolate to measure residual life.Therefore, it is different from the accelerated aging test across the whole span of material or component life.

Table 4: the definition of degradation mechanism, material and inefficacy

Accelerated ag(e)ing refers to accelerate to be exposed to produce end of life microstructure or the damaged condition of testing for sign subsequently.For example, the alligatoring of metal alloy microstructure can be accelerated to expose by the intensity and the toughness that reduce material.When relating to multiple-disruption mechanism (for example thermal mechanical fatigue), may need the test of accelerated ag(e)ing and accelerated aging to verify.Accelerated ag(e)ing can followingly realize: (1) improves temperature and load; (2) before testing, destroy product; (3) hold-time between raising exposes; (4) improve the concentration that causes deteriorated chemical agent.

Activated deterioration test is compared the advantage with analytical performance before material or component failure with accelerated life test.Deterioration test is measured in the material or is stayed how many life-spans in the parts, and this class understanding can prolongs life.When the extrapolation performance degradation reaches failure degree and can analyze deteriorated data to assess it.But only in the situation of the good Extrapolating model of setting up performance degradation and suitable performance failure, this alanysis is only correct.

For the situation that relates to multiple degradation mechanism, accelerated ag(e)ing should be carried out continuously: sample should be exposed under the condition that causes degradation mechanism one at a time gradually until reach the end of life situation.

Timeliness commercial and military aircraft is the significant concern item of U.S.Department of Defense (U.S. Department of Defense), NASA and the Federal Aviation Administration (US Federal Aviation Administration).These mechanisms all carry out the timeliness problem, for example corrosion and tired monitoring.Because they are exposed in the harsh and unforgiving environments, the candidate material of advanced subsonic aircraft and supersonic speed purposes is meaningful especially, comprises the fuselage material, for example aluminium alloy, aluminium-groundmass composite material, titanium alloy and polymkeric substance-groundmass composite material.The material that is used for the supersonic speed engine comprises nickel-based superalloy and pottery-groundmass composite material.Because their widespread use, aluminium alloy has large information database.

The degradation mechanism of aluminium alloy comprises: the variation of microstructure and composition; Time-dependent manner deformation and the destruction accumulation that causes; The acceleration effect of the temperature of environment invasion and attack and rising; Synergistic effect with above-mentioned mechanism.Using relevant failure mechanism (for example microstructure change, fatigue, creep, environmental effect) with the high temperature of aluminium alloy is presented among Fig. 7.

From the beginning, just need to know the parts predicted life at time t=0 place.According to particular case, the life-span can be about millions of cycles or several years.Life-span is depended on deterioration process, such as corrosion and fatigue, creep etc.Some parts, for example the flyer part reaches this system lifetim, and other stand tired parts and have much compact that life-span arranges.The purpose of accelerated test is the life-span of using the information obtain from the operational conditions that meets with stresses and test to determine main failure mode under normal running (operation) conditions.In order to realize this point, need to understand the mechanics of failure mode.In the situation of accelerated deterioration, temperature, load and load cycle have determined the life-span pattern of prediction failure mode.Can pass through to improve temperature, or pass through to improve load and load cycle, or come the accelerated aging test by the combination with all effects.Under the condition that meets with stresses, the prediction in several hours (or minute) of this model was lost efficacy.One empirical tests is used the life-span of same model prediction under the nominal operational conditions.

In the early stage design phase of parts or device, when not yet selecting hardware details and fixing not yet at last material to select, the task of top priority is to make this system " work ".Next consideration is the optimization of performance, and this refers to how to make this system to produce better result.Next step is to determine to improve the direction of product with up to specification.

On the other hand, life-span and failure mode and relevant in this article maintenance in the life-span with performance and soundness such as specification specifies.Shortcoming or because rigidity and crushing puncture, the inefficacy that replacing is necessitated owing to performance.In this respect, can use the accelerated test method to determine and prolongs life, but it also can be used for determining the improved direction of performance.

Correspondingly, accelerated test is by the material of the current test procedure predict future that carries out and the method for component capabilities.This obtains by using than the harsher testing circumstance that stands in normal environment for use.

Be known that equally Dean, Lee edits Degradation of Metals in the Atmosphere(ASTM Special Technical Publication//Stp), from in May, 1986 at Philadelphia, 1988 papers of the discussion of PA. holding, it provides the approach that obtains technical data from recent test, test of long duration program and test in place, comprises the data to new constituent material.

Be known that equally Environment Assisted Degradation Mechanisms in Aluminum-Lithium Alloys(the auxiliary degradation mechanism of environment in aluminium-lithium alloy), Gangloff, R.P.; Stoner, G.E.; Swanson, R.E. show (Univ.of Virginia, Charlottesville School of Engineering and Applied Science, 1988), it provides the summary that needs about the research based on the environment of the advanced aerospace alloys of aluminium and lithium-mechanical degradation mechanism.Reported the progress of three kinds of tasks of the aqueous environments that is intended to characterize alloy 2090 and gaseous state environmental corrosion fatigue crack growth kinetics, microstructure path and failure mechanism.Summarized to separate and measured the research that local process is target, supposed that this local process is to control corrosion and the embrittlement of aluminium-lithium alloy.

Be known that equally Atmospheric Exposure of Nonferrous Metals and (atmosphere of non-ferrous metal and alloy-aluminium is sudden and violent for Alloys-Aluminum:Seven-Year Data Reveal: seven annual datas),McGeary, F.L.; Summerson, T.J.; Ailor, W.H. show (Metal Corrosion in the Atmosphere-70th Annual Meeting, ASTM-STP-435,1967, the 141-174 page or leaf), it discloses the result of weathering test who four ASTM places in the U.S. is exposed 34 Aluminium wrought alloy in 7 years.In addition, for relatively, be included in the data that English five places expose other three aluminium alloys in 6 years.Expose in the British industry atmosphere of Sheffield and London and it is found that and produce maximum corrosion, particularly protect on the side at the quilts that are these plates that 30 degree angles expose with level., observe from limiting corrosive property on the weathering surface all in all test places in these two countries.As before the situation in ASTM B-3 that older aluminium alloy the carries out test (ASTM-STP-175), test continues also after 20 years again report.

Be known that equally Environment Assisted Degradation Mechanisms in Advanced Light Metals (environment in the advanced light metal is assisted degradation mechanism), Gangloff, R.P.; Stoner, G.E.; Swanson, R.E. show (Univ.of Virginia, Charlottesville School of Engineering and Applied Science.1989), it discloses search procedure, its roughly target be the forecasting mechanism of quantitatively characterizing alloy proterties and development environment failure mode.Present scheme comprises: the destruction location mechanism in the watersoluble chlorinated thing corrosion fatigue of aluminium-lithium alloy; Measurement and the mechanism of localization aqueous corrosion in aluminium-lithium alloy; The research of the localized corrosion of alloy 2090 and stress corrosion crack behavior; The deformation of aluminium-lithium alloy and fracture-dissolved oxygen effect and cryogenic effect; With the heat cracking growth in advanced person's POWDER METALLURGY ALUMINIUM ALLOYS.

Be known that equally Microstructural Degradation of Plain and Platinum Aluminide Coatings on Superalloy CM247 During Isothermal Oxidation (conventional aluminium compound and calorize platinum in the isothermal oxidation process on superalloy CM247 are coated with The microstructure of layer is deteriorated)D.K.Das, Manish Roy, Vakil Singh and S.V.Joshi work, (" Material Science and Technology ", October 1999, Vol.15, No.10, pp.1199-1208 (10)), its solid that passes through that discloses on the nickel-based superalloy CM247 of casting infiltrates the experiment that (pack cementation) technology is carried out, and comprises the common aluminide coating of high reactivity and the isothermal oxidation of calorize platinum coating under 1100 ℃, and its main purpose is the coating deterioration process in the system understanding oxidising process.Although exposing from oxidation, the weightening finish in conventional aluminium compound and the calorize platinum coating oxidation process follows at the very start para-curve kinetics, naked alloy is found out to show obviously very long initial instantaneous oxidation period (～20 hours), follows during this period parabolic law afterwards.For calorize platinum coating, constant para-curve speed it is found that than low about two magnitudes of common aluminide coating.Aluminum oxide is determined to be in the unique oxidation phase that all forms in most oxidation process-exposed on conventional aluminium compound and calorize platinum coating, although also find NiAl in the situation of the common aluminide coating above～200 hours ₂O ₄But the zone of oxidation on the naked alloy it is found that by Al ₂O ₃, Cr ₂O ₃And NiAl ₂O ₄Consist of.All find out three different stepss the conventional aluminium compound to have occured and the microstructure of calorize platinum coating in oxidising process is deteriorated, but for each coating difference.This deteriorated stage by stage of the final elimination that relates to phase diffusion layer in every kind of situation wherein disclosed in detail.

Be known that equally Oxidation-Induced Degradation of Coatings on High Temperature Materials:An Overview (induce bad by the oxidation of the coating on the high-temperature material Change: summary), Jedlinskia, Jerzy work (Proceedings Symp.Elevated Temp Coatings:SCI﹠amp; TECH, 1994, Vol.1,75-83 page or leaf), its interaction that discloses between erosion environment condition and the coating material causes the latter's accelerated deterioration.Understanding to degradation mechanism plays a key effect in having the design of material of improved character of use.The prior art situation that is used in the coating development field of the high-temperature use of oxidizing atmosphere is also disclosed.Also disclose main Types coating deposition program and degradation mechanism and for improvement of the approach of coating oxidation-resistance and the existing issue relevant with the protection of Ti base alloy and C/C matrix material.

Be known that equally Corrosion and Environmental Degradation (corrosion and environment are deteriorated), Schtze, Michael work; Editor: Robert W.Cahn; Peter Haasen (2000), its provide about whole theme-from ultimate principle to the current research result-comprehensively widely general introduction.It is write as by the top expert team in the world, becomes any material supply section scholar, physicist or the requisite bibliography of chemist of joining in corrosion science.Corrosion and non-corrosibility are one of most important problems in the Material Used science.Corrosion science not only sees it is important from economic angle, and because its interdiscipline of being combined with metallurgy, materials physics and electrochemistry, it also has very high scientific meaning.Nowadays, corrosion science even from Surface Science and polymer chemistry, obtain new power.

Be known that equally Environmental Degradation of Materials and Corrosion Control in Metals (corrosion control in the deteriorated and metal of the environment of material), M.Elboujdaini, E.Ghali edit (1999), and it comprises the paper that global professional shows and has summarized the corrosion of aluminium alloy, magnesium alloy and steel and the latest developments in the performance field.Far-reachingly except metal and the inhibition of stress corrosion crack, and corrosion monitoring, the state-of-the-art technology in spreading and testing.Problem comprises in detail: the inhibition of the corrosion behavior of aluminium alloy, aluminium and magnesium alloy and protection; The inhibition of metal and protection in the processing industry; The auxiliary cracking of steel: stress corrosion crack, corrosion fatigue and hydrogen loss; Electrochemistry and Monitoring techniques; The weather resistance of material: coating and performance thereof.

Be known that equally Role of Microstructural Degradation in the Heat-Affected Zone of 2.25Cr-1Mo Steel Weldments on Subscale Features during Steam Oxidation and Their Role in Weld Failures (microstructure in the heat affected zone of 2.25Cr-1Mo steel weldment is deteriorated in the steam oxidation process The effect of subscale pattern and the effect in welding seam failure thereof)R.K.Singh Rama work (Metallurgical and Materials Transactions, Volume 29A, No.2, in February, 1998), it provides by the electronics of weldment different zones and optical microscopy and has been characterized in the base metal adjacent with weldpool that causes in the welding process of 2.25Cr-1Mo steel, and namely the microstructure in heat affected zone (HAZ) is deteriorated.In order to study the deteriorated impact on the fouling kinetics in the steam and the subscale pattern that produces of microstructure, from weldment, extract base metal sample, HAZ and welding metal sample, and oxidation 10 hours under 873K in the environment of 35pct steam 1 nitrogen.Three regions and below subscale in the oxide skin that forms use scanning electron microscopy (SEM) and electron probe microanalysis (EPMA) sign.After deliberation " dissociating " the chromium content in three weldment zones on the protectiveness fouling with on the impact of subscale pattern.As principle achievement, this research has clearly show that the oxidation that occurs in the internal oxidation object area induces the crystal boundary cavitation corrosion in space formation and the adjacent area in the steam oxidation process of HAZ.Also disclosing oxidation induces the space to form and may act in inferior work-ing life of crystal boundary cavitation corrosion weld seam in the 2.25Cr-1Mo steel part.

Be known that equally Basic Types of Materials Corrosion That Designers The Must Be Able to Competently Address (material that the Designers must solve fully The base type of corrosion), Desi J.Kiss, M.S., (DJK Engineering, LLC is in internet site for the P.E. work Http:// djkeng.tripod.com/id3.htmlOn deliver), its disclose all material that can make available utensil, structure and transportation means all stand the corrosion.Various forms of corrosion all can affect any material.The most materials that can be used for load or bear heavy loading are metal or metallic, i.e. Steel Concrete.8 kinds of Corrosion Types comprise: stress corrosion crack, erosion-corrosion service, crevice corrosion, galvanic corrosion, intergranular erosion, evenly invasion and attack, spot corrosion and selectivity leach.Burn into corrosion control and the prevention of stainless burn into plastics, matrix material and pottery are also disclosed.

Be known that equally Microstructural Changes in Austenitic Stainless Steels During Long-Term Aging (little knot of austenitic stainless steel in the Long Term Aging Structure changes)Y.Minami, H.Kimura, Y.Ihara work (Mater.Sci.Techn., 2:795-806,1986), it discloses the research (304 hours, 316 hours, 321 hours, 347 hours and Niconmetal a-1) of microstructure change, precipitation behavior and the mechanical properties of typical austenitic stainless steel.Maximum 50,000 hours of steel static timeliness in 600-800 ℃ temperature range.Observe microstructure change by optics and transmission electron microscopy, and the resistates that uses x-ray analysis identification to extract.Make the Time-temperature precipitation figure of each steel.In the sample of 700 ℃ of lower timeliness, measure the amount of σ phase.Measure the tensile property of the variation of hardness and impact value and aging samples.

Be known that equally Decrease of Ductility in A1-10PCT Mg Alloys During Long-Term Natural Aging (A1-10PCT in long-term Natural Aging Process The ductility of Mg alloy reduces), Y.Kojima; T.Takahashi; And M.Kubo work (1981), the research that it provides the mechanical properties of A1-10pct Mg casting alloy in the about 13 years at most process of natural aging to change.Be less than in 3 months the sample greater than the elongation of 20pct in natural aging and only be down to 1 to 2pct through 10 years because of natural aging.By counter-rotating experiment and electron microscopy, it is found that this very big reduction of ductility causes owing to form spherical coherent GP zone in Natural Aging Process.Transmission electron microscopy (TEM) research shows that also the structure in GP zone appears as L1 (sub 2) structure, and wherein Al and Mg atom edge (100) direction is with the three-dimensional periodic alternative arrangement.

Be known that equally Degradation Due to Creep Deformation of 550 ℃ of 1CR-1MO-1/4V Steel at are (by the creep of 1CR-1MO-1/4V steel under 550 ℃ It is deteriorated that distortion causes), K.Kimura; T.Kisanuki; S.Komatsu work (Journal of the Iron and Steel Institute of Japan, 1985, Vol.71, No.15, the 1803-1810 page or leaf), it has described microstructure change and the deteriorated research of creep resistance that is caused by the creep fracture on the 1CR-1MO-1/4V steel that continues 9500 hours 550 ℃ of lower creeps.Especially, through and do not checked the impact of crystal boundary space on creep resistance through heat treated creep fracture sample again.Metallography is observed the microstructure change that has shown the three types under creep strain: the alligatoring of the carbide that usually occurs in drawing process, the formation of space and crackle, and near the remarkable recovery austenite grain boundary formerly.Carbide Coarsening degree even also slight in the tertiary creep stage, and can to ignore ground to the impact of creep resistance little in the space.The gradually loss of creep resistance be shown as with formerly austenite grain boundary near local recovery be closely related.

Be known that equally Role of Microstructural Instability in Long Time The Creep Life Prediction (work of microstructure unstable in long-time prediction creep life With), J.W.Jones, S.F.Claeys work (Pentagon Report D026031,1984), it has described the microstructure unstable to using Al alloy 6061 as the impact of long-time prediction creep life of cast material.By using accelerated ag(e)ing and short period of time creep test to measure the deteriorated impact on steady state creep speed of microstructure, measure the impact of microstructure change on the life-span in the long-time creep process.Under the middle equal stress of 260 ℃ and 288 ℃, the microstructure deterioration rate greatly affects creep life, and the method that other worker proposes can effectively be predicted creep life.Under low-stress, by complete overage sample is carried out the short period of time creep test and uses simple extrapolation technique, fully dope the creep life near 100,000 hours.The result shows, the understanding of the aging response of alloy can be with rational accuracy of the location estimate long-time creep life.

Be known that equally Fatigue and Damage Tolerance Behaviour of Corroded 2024 T351 Aircraft Aluminum Alloy (2024 T351 aviations of corrosion The antifatigue of device aluminium alloy and damageability)Al.Th.Kermanidis, P.V.Petroyiannis and Sp.G.Pantelakis work (Theoretical and Applied Fracture Mechanics, Volume 43, Issue 1, on March 1st, 2005,121-132 page or leaf), its described the antifatigue of 2024 T351 alloy samples of corrosion and damageability and with the comparison of this performance of uncorroded material.The sample of pre-etching carries out experimental study and comprises the derivation of S-N and the measurement of fatigue crack growth curve and fracture toughness property in degrading environment.Carry out the fatigue crack growth test for different stress ratio R.For corrosion sample not, all mechanical testings all repeat to obtain the reference material performance under identical condition.For the material that is corroded, cause the remarkable reduction of fatigue resistance and anti-damageability.Discuss the result of experimental study aspect the hydrogen embrittlement of inducing in corrosion and the corrosion of 2024 aluminium alloys.This shows needs to explain that the corrosion that prestores is on the impact of material character in the antifatigue of the parts that comprise corrosion area and damageability analysis.

The aluminium airframe is corrosion and fatigure failure easily, and this mainly interacts at structure contact place.Interaction between corrosion and the fatigue may consist of the serious threat of the structural integrity of flyer, especially along with flyer wears.The current consideration of the structure deterioration that corrosion is induced relates to the existence of corrosion and is accompanied by the reduction of the portative power of the structural element that is corroded, and the beginning of fatigue cracking.In corrosion-spot corrosion, will destroy quantize and relevant with the reduction of fatigue lifetime of the 2024-T3 sample that in the alternating impregnating corrosion process, is corroded.Consider that corrosion destroys the impact of situation and aircraft structural integrity to explain the beginning that destroys (MSD) from the multiple spot of pit on multiple spot.On the other hand, it is found that the fatigue crack growth speed of degrading the 2024-T351 sample before has no significant effect.

The corrosive attack of aluminium alloy has been classified as complicated oxidising process.The recent research of carrying out at a series of flyer alloys provides corrosion to be not limited to the evidence of known surface breakdown process, its appearance by the corrosion breach affects yield strength and fatigue lifetime, but this also is the origin cause of formation of the material hydrogen embrittlement of diffusion control.

For the 6xxx series that contains Mg, except oxidising process, the hydrogen that produces in corrosion process may spread and cause hydrogen-metal interaction in material.Nearest research shows that corrosion also may cause the hydrogen embrittlement of 2xxx, 7xxx and 8xxx aluminum alloy series.Although not yet fully understand the mechanism of hydrogen embrittlement process, identify different possible hydrogen and capture the site, this depends on alloy system.This Hydrogen Brittleness Phenomena is reflected as the remarkable reduction of the stretching ductility of the material area that is corroded.Explain the macroscopical hydrogen embrittlement that causes by the local microplasticity that hydrogen is induced.Use dislocation theory to explain this process.Pointing out, all is diffusion controlled process because corrosion and hydrogen embrittlement destroy, and the deteriorated part that is expected to be of the mechanical property of materials of mentioning occurs.But, at present, do not have experimental data and definite experiment and theoretical method for assessment of the regional local material performance number that is corroded of material.Point out, fatigue and the fatigue crack growth test of carrying out sought help from corrosion and tired interactional experimental study usually in some corrosive atmosphere, and without recourse to the test of carrying out at the pre-etching material, thus, the latter represents different situations, and a series of practice situation in crate more represent more relevant situation.

Antifatigue and the damageability of the aluminium 2024 T351 alloy samples of pre-etching under the viewpoint of the synergistic effect of corroding and corroding the hydrogen embrittlement of inducing, have been studied and have discussed.The experiment of carrying out comprises for the fatigue test that obtains the S-N curve, fatigue crack growth test and fracture toughness test.For the stress ratio R of different numerical value, carry out the fatigue crack growth test.In order to compare, all experiments are also carried out uncorroded material.The result has shown that existing corrosion explains that on the basic impact of the antifatigue of 2024 alloys and damageability and in the antifatigue in the zone that is corroded of structure and damageability are analyzed corrosion is on the needs of the impact of material character.

For being exposed to the A12024 T351 that degraded in the solution 36 hours, a series of measurements of spot corrosion density and dimple size have shown 2.586 * 10 ^-3The average spot corrosion diameter of mm and the spot corrosion density of per 100 square millimeters of 920 samples.Use the stereo-picture analysis to measure.The metallography corrosion characterizes and shows, degrades 36 hours for bearing, and also can expect some intergranular corrosions.Basic spot corrosion and the existence of intergranular corrosion have promoted the beginning of fatigue cracking substantially, and the fatigue lifetime of therefore significantly having reduced the sample that is corroded.As was expected, and the reduction of the fatigue lifetime of the sample that is corroded improves along with the reduction of fatigue stress.The fatigue endurance limit never 175MPa of corrosion material is down to the 95MPa of pre-etching sample.The matched curve of the material that does not corrode and be corroded all uses regression analysis to derive.

Under studied all situations, as if along with crack length increases, the decline of the fatigue crack growth property of the sample that is corroded is more faster than the fatigue crack growth property of uncorroded sample.It is reflected as obviously lower fatigue lifetime, obviously more early enters the sample that accelerates the crack growth zone and be corroded steeper curve in this stage.For the sample that is corroded, 3 seconds crack length was also less before losing efficacy, and this crack length that is considered to be formed in before the sample inefficacy of still be sure oing is measured.

Crack growth can be considered to increase progressively generation and tired corresponding to the material elements before having crackle now after the low cycle fatigue of some amount.Embrittlement is induced in corrosion by assessment material, and the Fracture Toughness of the material that is corroded is lower.The fracture toughness property that confirms the material that is corroded by the fracture toughness property method of masurement of discussing in next section reduces.Above-mentioned consideration can be explained and accelerate higher crack growth speed of crack growth stage and steeper crack growth raising.The Fracture Toughness of the reduction of the material that is corroded has been explained the crack length that reduced when losing efficacy, and also considers and is accelerating higher crack growth speed of crack growth speed stage, the fatigue lifetime of having explained the reduction of the sample that is corroded.

After deliberation corrosion and the corrosion hydrogen embrittlement of inducing on the antifatigue of 2024 flyer aluminum alloy specimens and the impact of damageability.Experimental result has shown the fatigue resistance of the material that is corroded and the remarkable reduction of anti-damageability.Under the viewpoint of the synergistic effect of corroding and corroding the hydrogen embrittlement of inducing, discuss acquired results.The result shows that for the reliable antifatigue of the parts that comprise corrosion area and damageability analysis the corrosion that the needs explanation prestores is on the impact of material character.

Be known that equally Corrosion-Induced Hydrogen Embrittlement of 2024 and, the 6013 Aluminum Alloys (hydrogen that the corrosion of 2024 and 6013 aluminium alloys is induced Crisp)P.V.Petroyiannis, Al.Th.Kermanidis, P.Papanikos and Sp.G.Pantelakis work, (Theoretical and Applied Fracture Mechanics, Volume 41, Issue 1-3, on April 1st, 2004, the 173-183 page or leaf), it discloses the impact of corrosion on the mechanical properties of typical flyer aluminium alloy.The result shows that corrosion exposes and causes the appropriateness of surrender and final tensile stress to reduce.In addition, even after short open-assembly time, also recorded the rapid reduction of lost efficacy elongation and strain energy density.The mechanical workout on the surface that is corroded it is found that has recovered surrender and final tensile stress, but does not have the ductility of restorer.The latter progressively returns to the value of uncorroded material after thermal treatment under the temperature corresponding with the thermal desorption in some hydrogen capture site.These discoveries clearly show that the corrosion of above-mentioned alloy is relevant with the volume hydrogen embrittlement.The rapid reduction of stretching ductility is relevant with the reduction of the residual strength of the material that is corroded.Use is associated the reduction of fracture toughness property and residual strength based on the model of multi-scale concept with reduction in corrosion and the strain energy density that do not obtained by tension test on the corrosion sample piece.Show, can use the residual strength of the parts that the strain energy density accurately predicting is corroded.

In order to evaluate and test the structural integrity of timeliness aircraft components, must consider corrosion effect, because the corrosion of aldural can cause catastrophic inefficacy with relevant hydrogen embrittlement.When the destruction of corrosion with other form, for example single fatigue cracking or multiple spot destroy when interacting, and can weaken the impact of corroding the hydrogen embrittlement of inducing.Organized many councils and international conference considering the material degradation problem in the old flyer, and a major issue is corrosion.The current consideration of the structure deterioration that corrosion is induced relates to the existence of corrosion and is accompanied by the reduction of the portative power of the structural element that is corroded.Not yet be fully recognized that the corrosion hydrogen embrittlement of inducing to the importance of structural integrity, this is still clearly underestimated.At present, be far from understanding corrosion and the hydrogen loss mechanism of aluminium alloy.Related destructive process occurs with atom level.The corrosion of aluminium alloy has been classified as complicated oxidising process.Test shows that in addition, the hydrogen that generates may be diffused into material internal and cause hydrogen in the concentrated and capture in the preferred capture site of depending on alloy system in corrosion process.

Majority research to the hydrogen embrittlement of aluminium alloy is carried out at the Al-Zn-Mg of 7xxx series alloy.Metastable aluminum hydride has been considered to the embrittlement intergranular fracture of the Al-Zn-Mg alloy that stands stress corrosion crack in water vapor is responsible for.

The preferential decohesion that contains the crystal boundary of the magnesium of separating out is that the difference of the intergranular fracture of these alloys is explained.Different aluminum alloys series, namely the hydrogen embrittlement of 2xxx, 6xxx and 8xxx is still underestimated and is not had an abundant document.In addition, do not admit fully also that even do not exist mechanical load also hydrogen embrittlement can occur, namely stress corrosion crack is unnecessary for hydrogen embrittlement.Evidence shows, what the hydrogen embrittlement that corrosion is induced may be to the toughness of tradition 2024 and 6013 alloys and advanced 2091 and 8091 alloys and ductility is rapid deteriorated responsible.Discharge with 6013 hydrogen in alloys and identify different capture sites and explain this deteriorated by quantizing 2024.By thermal treatment is corroded and uncorroded coupon utilizes these results capturing under temperature corresponding to site with the hydrogen of each checked alloy.

The fracture toughness property of the material that is corroded significantly reduces and must the evaluation and test local fracture toughness relevant with the reduction of strain energy density.The adding of multi-scale method is very effectively tackled hydrogen embrittlement that complicated mutual corrosion hydrogen embrittlement process and suggestion check that corrosion induces multiple spot is destroyed the impact of (MSD) problem, and wherein the distance of fixed orifices can cause the local volume embrittlement of material.

Carry out comprehensive experimental study with the impact on the mechanical properties of flyer aluminium alloy 2024 and 6013 of the hydrogen embrittlement that quantizes corrosion and corrosion and induce.Except tension test, also use pre-tired (MSD) sample of the otch that contains two holes of a row to carry out the residual strength test.Test corrosion and corrosion sample not.Use the multi-scale method with the reduction of fracture toughness property and residual strength with in corrosion be not associated by the reduction of the strain energy density of tension test acquisition on the corrosion sample piece.Also use widely fracture analysis to realize the confirmation that experiment is found.

The experimental research corrosion is on the impact of the mechanical property of flyer aluminium alloy 2024 and 6013.Obtain following results:

The degraded in mechanical properties that-corrosion is induced occured gradually with open-assembly time.Stretching ductility is down to extremely low end value by index law;

-in order to explain this result, need the multi-scale method so that the gap between the destructive process that occurs under the microcosmic grade and effect that the macroscopical mechanical properties of material is produced approaches;

The machinery in-the zone that is corroded is removed and has been recovered surrender and final tensile stress, but does not recover stretching ductility, and wherein the latter is only capturing just recovery after the thermal treatment under the corresponding temperature at alloy with hydrogen, and this shows that the corrosion of detected alloy is relevant with hydrogen embrittlement;

The fracture toughness property of-the material that is corroded significantly reduces; Must evaluate and test the local fracture toughness relevant with the reduction of strain energy density; With

The residual strength of the structure unit that-hydrogen embrittlement that can use the reduction evaluation and test of the strain energy density that is recorded by tension test to be induced by corrosion causes reduces.

Be known that equally Hydrogen Degradation of Ferrous Alloys (ferrous alloy Hydrogen deteriorated), Oriani, Richard A.; Hirth, John P.; Smialowski, Michael edits (William Andrew Publishing/Noyes, 1985, the 900 pages, ISBN 0-8155-1027-6), it provides basis, the mechanistic view of life of hydrogen-metal interaction to consider the phenomenological important summary deteriorated with mechanical properties.The hydrogen of structured material is deteriorated to be to have obtained in the past more and more serious problems of paying close attention between 50 years.The universal existence of hydrogen-source of corrosion in the aqueous solution, absorb in the pipeline of carrying moistening and contaminated hydro carbons and the pollutent in the melting process causes the importance of this problem.

Be known that equally The Effect of Hydrogen on the Structure and (hydrogen is to the austenitic structure of Fe-Me-Cr and character for Properties of Fe-Mi-Cr Austenite Impact), J.Burke; A.Jickels; P.Maulik work (Proceedings of an International Conference.Moran, Wyoming, 1976, the 102-115 pages or leaves), it is for the loss in ductility that absorbs relevant austenitic steel with gaseous state or the electrolysis of hydrogen.Although the susceptibility of this material is more much lower than ferritic steel and martensitic steel, in the situation that has absorbed high hydrogen concentration, mechanical properties deteriorated still remarkable.This has obviously hinted the application of material.In addition, nowadays induce the clear contact of setting up between the variation further to improve the meaning of the hydrogen embrittlement fundamental mechanism of understanding in these materials at the stress corrosion crack of some types and the hydrogen of structure and properties.The hydrogen embrittlement of austenitic steel can be divided into two large types: (1) high hydrogen fugacity, low diffustivity (being low temperature) cause serious internal strain, spontaneous transformation to become α ' and ε martensite and large intergranular and transcrystalline surface cracking with the combination of stabilization of austenite, and the combination of (2) composition, temperature and fugacity is not accompanied by the overall structure variation so that hydrogen is absorbed.

Be known that equally Decomposition of Carbides in 2-1/4Cr-1Mo Steels (carbide in the hydrogen attack process in the 2-1/4Cr-1Mo steel divides During Hydrogen Attack Separate), Shimomura, J.; Imanada, T. show (Scripta Metallurgica, 1985, Vol.19, No.12, the 1507-1511 page or leaf), it discloses by reducing Si content and has significantly improved anti-hydrogen attack in the 2.25Cr-1Mo steel, and greatly affects the composition of carbide and crystalline structure and explaining the impact of Si on hydrogen attack at carbide aspect chemical based on observing Si content.Also disclose the explanation about the variation of the carbide chemistry that occurs in the hydrogen attack process, and they have been associated from the deteriorated of mechanical properties in the 2.25Cr-1Mo steel with different Si amounts.

Be known that equally Hydrogen Attack, Detection, Assessment and Evaluation (hydrogen attack, detection, assessment and evaluation and test), R.Kot work (10th Asia-Pacific Conference on Non-Destructive Testing, 2001), it provides the summary of the detection of hydrogen attack in the steel, assessment and evaluating method.Under High Temperature High Pressure with H ₂The equipment of contact may stand hydrogen damage-Re hydrogen attack.Atomic hydrogen in steel easily diffusion and cracking may since under High Temperature High Pressure in the metal inside space CH ₄Or H ₂Formation.The loss that this causes crack and the decarburization of grain boundaries and is accompanied by intensity, this causes material unreliable or dangerous.Can use the degradation of the sound-damping qualities formed material mechanical properties in the bad steel of hydrogen loss.Known this point can be assessed the residual life of affected device.

Hydrogen has various harmful effect to metal.The metal that hydrogen is induced is deteriorated to be caused by being exposed in the atmosphere, and wherein hydrogen is absorbed on the material and causes the reduction of its mechanical property.Seriousness and the pattern of hydrogen loss depend on: hydrogen source-outside (gaseous state)/inside (dissolving), open-assembly time, temperature and pressure, may existence, types of alloys and the manufacture method thereof of the solution of certain reaction or solvent (for example acidic solution), the processing, final processing (for example nickel plating), heat treating method and/or remnants and the applied stress degree of metallic surface on surface (barrier layer, for example on metal as the zone of oxidation of hydrogen infiltration barrier layer) of interruption amount, exposure in the metal occur with metal.

According to combination and the quantity of above-mentioned variable, hydrogen loss can be categorized into hydrogen embrittlement, hydride embrittlement, solid solution hardening, subsurface defect generation, and can further be subdivided into various destructive processs as shown in Figure 8.

In hydrogen attack mechanism and prevention, hydrogen forms the methane bubble in material, and the carbon with steel reacts simultaneously.Forming the methane bubble on the crystal boundary and in slight void.The pressure of methane of setting up owing to expansion and the joint of this class bubble makes the space be extended to the crack.The growth in crack and space makes metal reduction and progress of fracture become large crackle.

The hydrogen attack degree depends on temperature, hydrogen dividing potential drop, stress level, open-assembly time, steel the Nomenclature Composition and Structure of Complexes.At plain carbon stool, low-alloy carbon steel with even be higher than in some stainless steels that move under the 473K and reported hydrogen attack.Hydrogen attack is one of subject matter in refinery, and wherein hydrogen and hydrocarbon stream are being processed under 20MPa and the about 810K level at most.In order to prevent giving birth to hydrogen attack at high temperature and/or elevated pressure, need high alloying element content.Use chromium (Cr), molybdenum (Mo), tungsten (W), vanadium (V), titanium (Ti), niobium (Nb) so that required resistance to be provided in steel, they are carbide forming elements.

Based on industry experience, API 941 ' s Nelson curve provides and generally has been used for the guidance that alloy is selected.Selected suitable alloy just be shown as temperature-hydrogen dividing potential drop coordinate the right or above curve, it has represented the expection operating parameters.

The anti-hydrogen attack of Effects of Heat Treatment steel.For example, easier generation hydrogen ftractures the 2-1/4Cr-1Mo steel of quenching and tempering owing to the low anti-hydrogen loss of martensite and bainite structure.Should avoid or carefully use the thermal treatment that produces excessive yield strength level.

Industry experience shows that the welding postheat treatment of Cr-Mo steel is of value to the hydrogen attack of resisting when using in the hydrogen environment.To be requirement hydrogen-hydrocarbon equipment manufacturers will own " low hydrogen " electrode before the running stores of welding carry out the embrittlement test and beginning to make be stored in the heat " box " in common practice.The weld cracking that the preheating requirement of low-chrome steel is caused being caused by hydrogen in manufacturing processed minimizes.In order to ensure final container or the anti-hydrogen attack of reactor, suitable inspection, quality control, good design and the manufacturing commercial city of standard are necessary.

Owing to being exposed in the hydrogen environment, steel causes hydrogen attack.Distress severity depends on open-assembly time, temperature, hydrogen dividing potential drop, stress level, steel the Nomenclature Composition and Structure of Complexes.For fear of/prevent hydrogen attack, should use the steel with the element that forms stable carbide.Should carefully apply thermal treatment to avoid producing the structure (martensite, bainite) with low anti-hydrogen attack.In the manufacturing processed of hydrogen and hydrocarbon processing equipment, suitable inspection and quality control system are necessary.Should provide the hydrogen loss of steel used in the shop equipment and hydrogen loss sample not for the hydrogen attack test-purpose.

Be known that equally Influence of Dissolved Hydrogen on Structure of Oxide Film on Alloy 600 Formed in Primary Water of Pressurized Water Reactors (dissolved hydrogen in the primitive water of pressurized water reactor, form on alloy 600 The impact of oxide film structure)Takumi Terachi, Nobuo Totsuka, Takuyo Yamada, Tomokazu Nakagawa, Hiroshi Deguchi, Masaki Horiuchi and Masato Oshitani (Journal of Nuclear Science and Technology, 2003, Vol.40, No.7,509-516 page or leaf), it discloses the result of study of the relation between dissolved hydrogen (DH) content in the primitive water of primitive water stress corrosion crack (PWSCC) susceptibility and pressurized water reactor (PWR) in the alloy 600.The structural analysis of the oxide film that for this reason, forms under four kinds of different DH conditions in the simulation primitive water of PWR uses grazing incidence X-ray diffraction meter (GIXRD), scanning electron microscope (SEM) and transmission electron microscope (TEM) to carry out.Especially, in order to carry out the Accurate Analysis of thin oxide film, GIXRD is used the synchronotron radiation of Spring-8.Oxide film mainly is made of nickel oxide under hydrogen-free condition.On the other hand, under 1.0ppm DH, form needle oxide.In the environment of 2.75ppm DH, oxide film has thin spinel structure.From these results and phasor consideration, approximately the condition of 1.0ppm DH is equivalent to stablize the border between NiO and the oxidation spinel, also is equivalent to the peak scope of PWSCC susceptibility.This shows that the border between NiO and the oxidation spinel may affect SCC susceptibility.

Be known that equally Internal Oxidation as a Possible Explanation of Intergranular Stress Corrosion Cracking of Alloy 600 in PWRs (as The internal oxidation of the possible explanation of the intergranular stress corrosion cracking of PWRs interalloy 600),P.M.Scott work (9 ^ThInternational Conference on Environmental Degradation of Materials in Nuclear Power Systems-Water Reactors, 1999), it provides the research to interior oxidation mechanism in the pressurized water reactor(PWR.In 1993 hydrogenated PWR primary water, oxidation is a kind of specious mechanism of intergranular stress corrosion cracking (IGSCC) at first proposing at Scott and LeCalvar.Carried out several times experimental study with this hypothesis of verification thereafter.The crackle and the secondary cracks that have adopted secondary ion mass spectrometry (SIMS) and analyzed in transmission electron microscope (ATEM) alloy 600 have been carried out some detailed microscopical determinations, and PRELIMINARY RESULTS is open.Disclosed is the viewpoint of some criticisms, and it comes from the suitability in typical PWR operating temperature and the lower inside oxidation mechanism of corrosion potential.Corrosion potential is equal to or less than the Ni/NiO redox potential, and this is the apparent speed that makes the intergranular diffusion of oxygen in nickel-base alloy and the cracking speed one of the observing particular problem that the thermodynamics of internal oxidation requires of making peace.If adopt this mechanism explain secondary side steam generator IGA/IGSCC, rear a bit meaningful especially.The second target is to be described in the form of the known example that oxidation is ftractureed in the intercrystalline under the comparatively high temps, in order to provide reference point to other paper that relates to crackle in the alloy 600 of making under detailed inspection reality or the prototype PWR condition in this meeting.

Be known that equally (aluminium closes Corrosion and Protection of Aluminum Alloys Corrosion and the protection of gold),V.S.Sinyavsky, V.D.Valkov and V.D.Kalinin work (Moscow, Metallurgia, 1986), it discloses aluminium alloy has been imposed various types of corrosion (depending on working conditions, alloy composition etc.).The corrosion of these types comprises corrosion cracking, intergranular corrosion and degrades.The aluminium alloy of some cuprics tends to intergranular corrosion.This corrosion occurs in the magnesium and silicon contained aluminium alloy sometimes.

Because incorrect thermal treatment and sometimes since in such as the multiple environment of seawater, marine products and industrial atmosphere long-time the exposure in the sun, the intergranular corrosion of generation aluminium alloy.The intergranular corrosion theory thinks that in the artificial aging treating processes of aluminium alloy or under other heat effect of making, Al-Cu sosoloid at first destroys and accompany by precipitation at grain boundaries in 90 ℃ to 270 ℃ lower heat treatment processes.Sedimentary composition is near intermetallic compound CuAl ₂This has produced copper and has reduced the zone near crystal boundary.In crystal grain, intermetallic compound is precipitated to less degree, therefore the less copper that exhausts of sosoloid in the zone of moving from crystal boundary.Because the heat effect in the said temperature scope, from electrochemical viewpoint, it is uniform that the surface of aluminium alloy no longer is considered to.Potential difference at crystal boundary and intergranule is up to 100 millivolts, and this has finally caused galvanic corrosion.

Usually aluminium alloy is imposed suitable thermal treatment (it provides favourable Potential distribution on whole surface) and suffer intergranular corrosion to prevent aluminium alloy.Correct thermal treatment makes alloy more even, and copper is transferred in the sosoloid as much as possible, and it can be fixed by quick sudden cold process.When sudden cold cold water (40 ℃) under 480-500 ℃, and further during natural aging, duralumin has optimum corrosion resistance.

Corrosion cracking when alloy is corroded environment and static action of pulling stress simultaneously.This stress can be outside, is again inner.Some aluminium alloys are easy to occur stress corrosion crack.Alloy depends on the character of metal construction, size and stress and corrosive atmosphere for the being subject to property of this type of dangerous corrosion failure.The corrosive atmosphere of targeted attack alloy helps corrosion cracking.

Degrading is a kind of subsurface corrosion of specific type, and it mainly is parallel to deformation vector development, in the semifinished part moulding, produce, and accompany by that the crackle that the party makes progress generates, the peeling off or the fully damage of sample or parts of single metal particle.This corrosion can develop along the distortion border of crystal boundary or dendrite structure cell, and the transcrystalline development.Degrade the feature of the semifinished part that basically is distortion.Under some abnormal conditions, it can (for example, having in the Al-Mg-Li alloy of high Mn content) be observed in the traditional casting that adopts directed liquate.

Degrade concrete structural state, second-phase and solid solution crystals orientation, alloying element or impurity and uneven distribution, the internal stress of high-content and some the physics and chemistry state that depends on the surface of corrosive environment character on the deformation direction that be attributable to.

Therefore, by the erosion resistance of the aluminium alloy in the following standard test use: the concrete structure of the alloy of surface smoothness, internal compressive stress (favourable) and near surface, this aluminium alloy is made by certain sudden cool condition.Under optimum condition, be applied to the supersound process of this aluminum alloy surface very likely in conjunction with above-mentioned all favorable factors.

Be known that equally Corrosion of Aluminum and Its Alloys (aluminium and alloy thereof Corrosion),V.V.Gerasimov work (Moscow, Metallurgia, 1967), it discloses aluminium electrochemistry performance and the erosion resistance that highly depends on metallic impurity.The erosion resistance of this aluminium alloy depends on character and the quantity of alloying element.Be lower than under 100 ℃ the temperature, fine aluminium has maximum erosion resistance.Do not containing activating ion, for example in the water and neutral environment of halogen, the steady potential of fine aluminium is in inertia area.Therefore, under this type of condition, the erosion resistance of aluminium is quite high.

The alloying of aluminium has changed the dynamics of anodic process.Iron level is that the steady potential of 1% alloy is in inertia area.This has determined the quite low erosion rate of this type of alloy, although it is higher than fine aluminium.In 3% sodium chloride solution, the proportional rising of the erosion rate of this alloy and iron level (since 0.004%).

The influence degree of the dynamics (aluminium alloy solution) of the alloying antianode process of aluminium and copper is greater than the situation of iron.When copper content improves maximum 0.01%, observe and slightly improve aspect the erosion rate in 3% sodium chloride solution.Along with the further raising of copper content, corrosion process significantly strengthens.

Hydrogen and oxygen over have been reduced with the aluminium of nickelalloy.Accelerate to have improved the steady potential of alloy because introducing cathodic process that nickel causes.Contain the standard potential of alloy of 0.2% nickel corresponding to passive state zone; Erosion rate in the case is low.Along with nickel content surpasses 0.6%, steady potential is corresponding to the transpassivation zone; Erosion rate raises naturally.

Therefore, for aluminium, the highest 1% alloying element content has maximum impact to the dynamics of electrode process.When forming alloy with iron, copper or nickel, aluminium alloy contains the intermetallic compound (intermetallide) of these elements.The electropotential of intermetallic compound is more positive than the steady potential of aluminium, and plays negative electrode in aluminium alloy.

The manganese of the maximum 1-2% of content, zinc, magnesium and silicon can not strengthened corrosion process.When zinc content brings up to maximum 25%, move to cathode direction in the steady potential of neutral and sour environment interalloy.The impact that the steady potential of this alloy is not further improved by zinc content in fact.Add 0.16% zinc anticathode process rate in the aluminium and almost do not have what impact.Therefore, the zinc alloy aluminium with maximum 2.05% can not improve, even slightly reduces erosion rate.

Amount mostly is 5% magnesium most can not significantly improve Corrosion of Al.Under neutrality or sour environment, when aluminium and magnesium alloy chemical, steady potential reduces.Identical is the situation of using lithium.

Under neutral environment, the standard potential of aluminium in fact is not subjected to the impact of silicon; Under sour environment, its rising.In fact silicon in the sosoloid do not affect Corrosion of Al, although can there be local negative electrode in the silicon intermetallic compound, and accelerated corrosion.Notice that silicon looks the protective value that has significantly improved the lip-deep sull of aluminium, because aluminum silicon alloy-type alloy is very corrosion resistant.Under sour environment, the sodium content in 0.035 to 0.078% scope is very harmful to the tolerance of aluminium.Sodium content maximum in the aluminium that contains the 0.3-0.4% iron contamination should be between 0.02 to 0.03%.If be present in the aluminium, sodium has been strengthened intergranular corrosion.

0.08% calcium contents has reduced the tolerance of industrial aluminum under the neutral environment slightly; The sodium of 0.5-1.0% has significantly accelerated Corrosion of Al in the basic solution of 0.5-n (n represents the concentration of solution).Calcium impurities is especially dangerous in the presence of silicon.

The detrimental action that has suppressed copper with cadmium alloy aluminium.Plumbous almost not effect of tolerance to aluminium.Be higher than 0.01% titanium content and strengthened corrosion under sour environment.Cerium, cobalt, platinum, silver, thorium and vanadium have disadvantageous effect.For example, the aluminium that contains 40% silver medal namely damages (failed) fully in test under 100% relative humidity (RH) atmosphere after several days.By effectively making Ag ₂The Al intermetallic compound plays the effect of negative electrode, has caused high erosion rate.In some instances, chromium, tin and cadmium do not have effect, but they add deep-etching sometimes.Antimony improves the erosion resistance of aluminium.

Even a small amount of mercury also causes the amalgamation of aluminium, the dissolving metal speed of metallic surface depassivation and raising.Mercurous aluminium protector has fully negative current potential, and in fact not in time and passivation.

Alloying affects steady potential and erosion resistance to the dependency of pH environment.Under alkaline environment, fine aluminium and most of aluminium alloy are not corrosion resistant.Under this condition, the alloy of 0.5 magnesium that mixes has minimum erosion rate.When aluminium and magnesium alloy chemical, generate sull in the metallic surface.This film contains magnesium hydroxide, and it is insoluble in the alkali.In the alkali of dilution, alloy corrosion resistance improves with Mg content and improves.In dense alkali, magnesium can not improve the erosion resistance of aluminium.Improved erosion resistance in ammoniacal liquor with the alloying of magnesium and manganese.In containing the coke water of ammoniacal liquor, the aluminium of 99-99.5% and contain 1.25% manganese or the aluminium alloy of 3% magnesium is corrosion resistant.

In non-oxidizing acid, silicon has been strengthened Corrosion of Al, and cadmium has suppressed Corrosion of Al.Zinc and manganese have disadvantageous effect.Magnesium and tin have improved erosion resistance.In single-phased alloy, 1% silicon can not reduce the erosion resistance of metal in nitric acid; In polyphase alloy, 1% silicon has significantly reduced the erosion resistance in 65% nitric acid.Content is 1% copper, even not exclusively be dissolved in the aluminium, also can significantly strengthen the corrosion in 25% acid.

In 5% and 10% hydrochloric acid, 99.996% aluminium and to contain the aluminum alloy corrosion resistant of 0.5% magnesium fairly good.Erosion rate in these cases is no more than 3-5 gram/rice ²My god.Under equivalent environment, 99.5 Corrosion of Al speed is respectively 352 and 7780 grams/rice ²My god.

Impurity and alloying element have unusual effect for the spot corrosion in aluminium and alloy thereof.In 99.99% aluminium, in fresh water, seldom observe Corrosion of Al.But in the aluminium of 99.5-99.8%, can reach 0.3 millimeter in all internal corrosion degree of depth.Aluminium purity is reduced to the 99% cathodic process speed that has improved in oxygen ionized zone by 99.99%, and has improved the speed of restriction diffusion current and hydrogen ion discharge.This has strengthened spot corrosion.

Local corrosion has been strengthened in the effect of local negative electrode.Iron and copper content are higher, and quantity and the degree of depth thereof of corrosion pit are larger.Corrosion pit is usually directed on the rolling direction of arranging corresponding to intermetallic compound.Also observe spot corrosion in the scored area of exposing intermetallic compound.

When in boiling water, processing the aluminium surface, reason whatsoever, protective membrane has recovered in its weakened zone.This type of processing has improved the tolerance of alloy to spot corrosion.

Various surface treatments, as roll rear degreasing, etch in 10% alkali, chemical rightenning in the mixture of phosphoric acid and nitric acid, for the not impact of the erosion resistance under 53-70 ℃ in distilled water of 110 alloys.In chloride soln, surface finish has reduced corrosive wear.In the potassium sulfate solution of 0.001-1.0-n concentration, the aluminium that polished in fact can not corrode.Chemical rightenning has reduced by 20 times the corrosion of 99.5% aluminium under 87%RH atmosphere.

The surface treatment of aluminium alloy affects them to the proneness of spot corrosion.As the result of preliminary etch (preliminary etching), at 2S and 3S alloy (the wrought aluminum alloy that the U.S. uses; New title is respectively 1100 and 3003) degree of depth of upper spot corrosion improved 10-50 times when test in fresh water.

The plastic deformation that destroys impure intercrystalline material integrity has improved the intergranular corrosion resistance of the aluminium that mixes with iron and nickel.Before quenching and timeliness, use lower Heating temperature, can reduce intercrystalline internal adsorption or the collapse of grain boundaries sosoloid.

Under the combined action of corrosive atmosphere and mechanical stress, some aluminium alloys for example with the alloy of magnesium or magnesium and zinc doping, are commonly referred to the invasion and attack of the special shape of corrosion cracking or stress corrosion.Usually in containing muriatic environment, observe the invasion and attack of this form.The corrosion cracking of aluminium alloy can be interpreted as intermetallic phase Mg ₂Al ₃Precipitate at crystal boundary.Can find that this intermetallic compound is present on the crystal boundary of the magnesium adulterated al alloy that suffers corrosion cracking by metallographic and electron microscopic organon.

Mechanical stress produces submicroscopic breach and crackle in this intermetallic compound, impel corrosive environment to infiltrate β-phase, and has strengthened the decomposition of this phase.In addition, tensile stress impels that β-grain boundary precipitate hands down.

The Among Materials, Mechanical And Corrosive Factors During Corrosion Fatigue of the aluminium alloy that magnesium mixes is as follows.The β of grain boundaries-in chloride soln, do not have passivation, and strong dissolving.This intermetallic compound can or precipitate under tensile stress in the manufacturing of alloy and treating processes.The dissolving of β-phase and the generation of submicroscopic cracking have caused generating the concentrated and precipitation of new intermetallic compound.Therefore, this process strongly spreads and is deep in the metal.

Environment degasification or cathodic polarization make current potential move to cathode direction, and reduce the dissolving of β-phase, have reduced thus Among Materials, Mechanical And Corrosive Factors During Corrosion Fatigue.Anodic polarization or contact the dissolution rate (it does not have passivation in muriate) that has improved β-phase with more expensive metal (copper, stainless steel), and therefore aggravated corrosion cracking.When etch alloy surface in acid or alkali, Among Materials, Mechanical And Corrosive Factors During Corrosion Fatigue is the fastest.Surface finish has prolonged alloy to the life-span of losing efficacy.When pH is increased to 6 by 0, sample is to the Service life that lost efficacy.The aluminium alloy of magnesium and copper of having mixed is simultaneously compared with magnesium-copper binary alloy and is not produced so easily corrosion cracking.The additional alloying with 0.5-1.5% zinc has improved the corrosion-resistant cracking behavior of the alloy that contains 7-8% magnesium; Tempering temperature and deformation degree have been brought up to the value of the easy corrosion cracking of alloy.

Under the effect, alloy can be owing to corrosion fatigue was lost efficacy in corrosive atmosphere and repeated load.Because corrosion fatigue, muriate has accelerated the inefficacy of aluminium alloy.In 3% sodium chloride solution, the safe range of stress of 2024 alloys is 10 ⁷Lower 3.5kg/mm ²

In closed system, inhibitor begins to be widely used to protect metal and alloy not to be corroded.Some oxygenants, for example chromic salt and dichromate are used as the corrosion inhibitor (passivator) under the neutral environment.At low temperatures, chromic salt is used for protecting under neutrality, alkalescence and weak acid environment aluminium and alloy thereof not to be corroded.If add Sodium chromate or the potassiumchromate of 0.5-1.0 grams per liter in containing the water of 50-100 mg/litre salt at the most, the erosion rate of aluminium and alloy thereof will reduce greatly.Along with the increase (especially copper) of salt concn, the chromic salt protective value reduces, and spot corrosion occurs.

Some other compound is used as inhibitor with the aluminium parts in the protection cooling system.Thus, contain adding 3% SODIUMNITRATE, 0.03% sodium phosphate and 3% sodium acid phosphate in the muriatic river of 35 mg/litre under 80 ℃, erosion rate reduces 2-3 doubly; Add 0.03% SODIUMNITRATE and water glass, 3% Sodium Benzoate, corrosion reduces 6-8 doubly.

G.V.Akimov has proved the electro-chemical protection of duralumin.Range estimation shows 4 meters long duralumin sheets, is fixed by the zinc band endways, and is rear without any corrosion failure in the seawater test.With cross over muriate-silver electrode-cathodic polarization of 0.8V current potential protected the duralumin in the seawater in 6 months.Under ocean environment, do not corroded by protective material protection duralumin hull.The magnesium protective material is evenly distributed in hull bottom, and is bolted on the vinyl plastic backing strap with the steel of zinc coating.

Be known that equally Chemical and Electrolytic Treatment of Aluminum And Aluminum Alloys (chemistry of aluminum and its alloy and electrolysis treatment),S.Vernik and R.Pinner work; B.A.Zelenova and N.I.Veselova translation editor (Sudostroyeniye; Leningrad, 1960), it discloses the erosion resistance that can significantly improve by the coating supercoat in some cases aluminium alloy.For aluminium alloy, general custom is to form oxide film by oxidation or anodizing.Anodizing has improved aluminium and the erosion resistance of alloy under industrial atmosphere thereof greatly.Best oxide film is that thickness is 0.0025 to 0.015 millimeter and the oxide film by obtaining in sulfuric acid and the polarization of oxalic acid middle-jiao yang, function of the spleen and stomach for aluminium.This type of film can be through benefiting from the test in a year under the 20% sodium-chlor spraying condition.

Generate the protective oxide film on the aluminum alloy surface in the time of can at high temperature in water or the aqueous solution, processing metal.Can be by realizing the high corrosion resistance of aluminium alloy in seawater with fine aluminium coating.This coating not only with alloy and corrosive atmosphere isolation, has also been protected alloy by electrochemical method.In order to protect aluminium alloy not to be corroded, can adopt the glazing method.Enamel is very durable in water, acid, weakly alkaline sanitising agent and urban air.Pitch, polymkeric substance and paint coating, and grease is used for aluminium and alloy thereof in the corrosion prevention of atmosphere and soil.

Be known that equally Corrosion Theory and Corrosion-resistant Structural Alloys (erosion theory and corrosion resistance structure alloy), N.D.Tomashov and G.P.Chernova work (Moscow, Metallurgia, 1986), it discloses for the damage of metal when at high temperature being contacted the inclusive NAND ionogen by metal and dry gas and contact, and chemical corrosion mechanism is representational.When this occurs, to compare with galvanic corrosion, oxidation-reduction reaction occurs with the single incident form.In part in turbo-jet engine and rocket engine, in the power house etc. and the operational process of structure, in the metallurgical operations in the metal heat treatmet process, gaseous corrosion is possible.

The ability that metal is at high temperature resisted the attack of gas is called thermotolerance.Metal another key property at high temperature is hot strength, and it has defined material keeps good mechanical properties under this type of condition ability.This metal can be heat-resisting, but does not have good hot strength (for example, the aluminium alloy under 400-450 ℃).Under 600-700 ℃, high-speed tungsten steel is heat-resisting, but also non high temperature is strong.

According to the interaction between following formula generation metal and the oxygen (burning): Me+O ₂=MeO ₂The oxygen molecule that arrives metal is adsorbed, and is namely caught by its surface.The absorption of oxygen in metal is usually as follows.Physical adsorption occurs on the clean surface, weakens the key between Sauerstoffatom and the molecule.Molecule breaking, Sauerstoffatom attracts electronics there from atoms metal.The O that moves and generate towards oxygen when electronics ^-2The chemisorption stage occurs during the nuclear of the metal-oxide compound (oxide compound) that ion equals to generate.The product of oxygen-metal interaction (oxide compound) provides the surface with oxide film, and this oxide film has reduced its chemically reactive.Depend on thickness, the film on the metal can be categorized as thin (invisible) of maximum 40 nanometers of thickness, common (by tempering color as seen) of thickness 40-500 nanometer, or thickness surpasses the thick of 500 nanometers.For example, in the situation of aluminium:

-in dry air, several days caudacorias are 10 nanometer thickness;

-under 600 ℃, 60 hours caudacorias are 200 nanometer thickness;

During-anodizing, film is 3 to 300 micron thickness.

For metal and alloy, gaseous corrosion is subjected to the impact of external factor and internal factor, the turnover rate of external factor such as gas composition, pressure and atmosphere surrounding, temperature and heating condition, the character of internal factor such as alloy, chemistry and phase composite, mechanical stress and deformation.

The protective value of oxide film depends on character and the composition of alloy basically.Chromium, aluminium and silicon significantly postpone the oxidising process of steel, and this is owing to generated the film with high protective value.The deformation of metal in heat-processed causes film discontinuous, has improved thus rate of oxidation.Only be lower than under the temperature of recrystallization temperature, preliminary deformation has no impact to rate of oxidation.

For the gaseous corrosion protection, use refractory alloy, protective atmosphere and protective coating.

Be known that equally Corrosion and Corrosion Protection (protect by corrosion and corrosion Protect), F.Todt work (Khimiya, Leningrad, 1967), it discloses electrochemical corrosion course is the combination of two coupling reactions: anodic reaction (oxidation) Me=Me ^Z++ ze; Cathodic reaction (reduction) D+ze=(Dze); Wherein D is the depolarizer (oxygenant) that attracts the z-electronics (ze) that discharges because of anodic reaction (metal electric from).The diagram of electrochemical corrosion course is seen Fig. 9.

The total surface of actual alloy is inhomogeneous, that is to say, the zone that exists current potential to differ widely.The metallic surface is aspect the microirregularity of structure different (crystal boundary, impurity) only, but also can be aspect the sub-micro roughness different (defective of crystalline structure, the impurity atoms in the lattice etc.).This makes the Anodic and cathodic processes localization, and causes growth (for example, the growth of spot corrosion)---the intreractive theory of little electric element under galvanic corrosion of local corrosion.

Modern galvanic corrosion is theoretical, and the dynamics that is called galvanic corrosion is theoretical, emphasizes to damage when the electrochemistry that phase time in the middle of metal-ionogen occurs and can occur metal.The fact of corrosion does not depend on electrolyte property, no matter is in the situation of ultrapure water or concentrated aqueous solution.Electrolytical amount neither be so important: the moisture film that can be several micron thickness.The unique conditional that corrosion occurs be metal electric from the possible combination of cathodic reaction on the metallic surface of reducing of anodic reaction and part metals or other lewis' acid.If the equilibrium potential of anodic reaction is more negative than the equilibrium potential of at least a possible cathodic reaction, be this situation.(stablizing) current potential that produces in the case will be got the mid-way.Irrelevant with form of corrosion, should satisfy this condition.

When immersion metal is in the electrolytic solution, between metallic surface and ionogen, there is the certain potential difference that produces because generating electrostatic double layer, namely in the asymmetric position of the particle at metal-electrolyte interface place.

Figure 10 and 11 shows the diagram that electrostatic double layer generates, and Figure 10 shows that the atoms metal ion is transformed in the solution; Figure 11 shows that positively charged ion is transformed into the metallic surface from solution.

When being enough to destroy the key between metal ion-atom and the electronics, metal ion is transferred in the solution when ionic hydration energy (ion hydration energy), and the electronics of equivalent is stayed the metallic surface, makes metal watch wear negative charge.In addition, these negative charges attract metallic cation from solution.The electrostatic double layer that this has caused at metal-electrolyte interface place has caused potential difference certain between metal and the electrolytic solution.

The another kind of variation is possible.On the metallic surface, positively charged ion can be discharged (bond energy in the lattice is greater than hydration energy) from electrolytic solution.As a result, the metallic surface obtains positive charge, and forms electrostatic double layer with the solution negatively charged ion.

Electrode potential value greatly affects the character of corrosion process.Corroding the current flowing of infinitesimal between action period in poor having caused of the initial potential between anode and the negative electrode.When corrosion current flowed after the circuit sealing, potential difference reduced.This type of potential variation as the current flowing result is called polarization.

Depend on the electrode process on the negative electrode, galvanic corrosion can be categorized as with Types Below: employing hydrogen polarization (hydrogen ion is regenerated at negative electrode)-in acid; Adopt oxygen regeneration-air, in water, in salts solution, etc.; Or adopt the regeneration of other oxygenant.

Passivation is the relatively high corrosion-resistant state that the anodic reaction delay of metal ion in the certain potentials zone causes.When contacting with strong oxidizer, metal usually produces passive state.But for some metals, even water also is great oxygenant (for example titanium).The film theory of passivation is still one of basic theory.A kind of adsorption theory is arranged, and it is thought, because passivation occurs in the absorption of oxygen in the metallic surface.Have been found that in addition when the amount of the oxygen of absorption so that passivation still occurs in surface even can not be covered by the thick layer of molecule the time.Blocking-up active surface region interpretation this phenomenon, it is restricted.

Be known that equally Corrosion Cracking and Protection of High-strength Steels (corrosion cracking of high-strength steel and protection), F.Azhogin work (Moscow, Metallurgia, 1974), it discloses, and corrosion cracking is possible under the combined action of corrosive atmosphere and tension stress.The edge is perpendicular to the plane of tension stress, along crystal boundary (it is in the low state of stress that is subjected to usually) and intracrystalline development usually for crackle, and it is especially typical for corrosion cracking and corrosion fatigue.In corrosion cracking, tough metal is subject to significant brittle rupture.Suggestion about corrosion cracking mechanism is that opinions vary.

Adsorption theory proposes, and the solution Anion-adsorption is on movably dislocation and other textural defect.This has reduced surface energy, and has promoted the fracture of atoms metal key.As the result of the wedging action of surfactant in the absorption in the microcrack on the metallic surface, crack nucleation (again binding effect) occurs.Some investigators think that the corrosion cracking of charcoal and stainless steel, titanium and its alloy can be owing to the hydrogen adsorption at progressive crack tip place, and it has caused the local embrittlement of metal.

Electrochemical theory thinks that the principal element of crack growth is the metal anode dissolving of accelerating in crackle bottom (base).The main focal point of stress that produces on the test button surface of tensioning (it can not relax easily in high-strength material) can cause at this some place passivation destruction and electrochemical dissolution more at a high speed because of some textural defect.The negative electrode of this electrode pair is the side surface of crackle and the part outside surface of sample, and anode is crack tip.Highly the dissolution process of localization has kept the acutance of crackle in atomic level, and has therefore kept maximum stress to concentrate at crack tip.The atom dissolving of crack tip is the groove (notch) of slit or structural block probably, and it produces with relatively low linear velocity.At certain in a flash, the fault block by having high linear velocity or the brittle rupture subsequently in slit realize this groove, but possible delay in next fault block or crystal grain are mobile has slower electrochemistry groove subsequently again.In the microcosmic scale, crack growth will occur quite unevenly, until replacing of electrochemistry groove and mechanicalness damage is too frequent, to such an extent as to it becomes the avalanche type brittle rupture of sample nubbin.

Undoubtedly, do like this, the process that accompanies of strengthening the development of crackle and corrosion cracking is as follows: the metallic surface is at suction hydrogen and the hydrogen embrittlement in pre-destroyed area of crack tip, the reduction (wedging effect of Rebinder) of absorption aspect intensity, high strength and alloy low ductility therefore, since relaxation process order in elementary stress concentration in the heart stress concentration can not reduce, ununiformity (little inclusion of the microstructure of the alloy of promotion generation stress concentration center and elementary crackle, the sub-micro imperfection of structure), the character of dislocation, little distortion and atomic lattice are in the collapse of crack tip.If stress is not too high, alloy has the so perfectly passivation isolation of impurity (for example because of) at crystal boundary, and crackle will develop at intercrystalline.Otherwise intercrystalline crack growth occurs.The situation of most of corrosion crackings can be explained on the machinery of combination-electrochemical mechanism basis in more detail.

At first, in main crack, the chances are is interacted by the chemisorption between the active environment ion of separating metal near surface for basic role in the appearance of focal point of stress and growth thereof, and cause non-homogeneous deformation (dislocation) distribution at the stress concentration center of local surfaces activation and tensioning state to be played the part of.

In addition, by the tension force of lattice in the machinery raising crack tip zone, crackle is along with the continuous activation growth of anodic process.If the initial state of metal is corresponding to passive state, this activation is especially high, and the overlapping local activation that causes at the crack tip place of tension force.In the end the stage, macroscopical physical disturbance increases in the snowslide mode, and fracture under the condition when mechanical factor is dominant.

In corrosion cracking, mechanical stress and corrosive environment have caused doing respectively much bigger metal strength loss of time spent than these factors by simultaneously effect.Corrosion of metal cracking is early well known in practice under many environment, for example, and such as the so-called season cracking of the brass product of prolong, brass box, rifle shell case; And such as the corrosion cracking of the product made from steel such as water screw, bar, diesel engine, turbine blade.

Nitrogenous soft steel is very easy to the corrosion cracking.Nitrogen is obviously relevant with the change of internal stress to the effect of High Strength Steel corrosion cracking.Nitrogen and α-iron and γ-iron forms interstitial solid solution.In steel, introduce titanium and help nitrogen to be combined in the strong nitride, and prevent from generating interstitial solid solution, reduced internal stress, improved the corrosion-resistant cracking behavior of High Strength Steel.

Be known that equally Metal Fatigue (metal fatigue)(Symposium, Moscow, Inostr.Literatura, 1961), it discloses fatigue is the process of destroying gradually accumulation, finally forming crackle and rupture fully in the material under repetition or repetition variable stresses.This process is of paramount importance to be characterised in that, carries out the method under the stress that is significantly less than (twice or higher) tensile strength (it is the intensity of measuring) under static load.The ability (it is called endurance) that the metal opposing repeats changing load is significantly less than static strength.The main of metal resistance to fatigue is safe range of stress.Under similar test conditions, determine fatigue strength by chemical constitution and the internal structure of metal, it depends on production technique.At the different times of fatigue process, character and the metallicity of structural changes are as follows:

(1) tired latent period-in little surrender stage, dislocation source begins to act on single crystal grain and mainly works in the upper layer of sample.In the surrender stage in cycle, whole volume of sample is included in the plastic deformation.Dislocation begins strong propagation and in the born of the same parents' structural interaction that forms.Slip band appears at specimen surface.Periodically reinforcement is the last stage during fatigue is hidden.The what is called shorter than crystal grain cross section stablized slip band and appeared on the specimen surface.These incapabilities are eliminated by the upper layer of removing several micron thickness, and the slip band that produces under static deformation simultaneously can be removed by photic polishing.Arrived the latter stage of strain, submicroscopic cracking is opened and be converted into to these bands.

(2) the saturated and dislocation structure conversion of submicroscopic cracking evolution period-dislocation desity: many crystal grain (mainly being to approach the surface) have and draw to get very long structure cell, and its wall can be compared with grain-size.This class formation is called band structure.To the end in the second period, the net of the submicroscopic cracking that the whole surface coverage of sample is dense, but it does not exceed crystal boundary.The at present damage of accumulation can't be thought irreversible, so they do not have serious reduction to the tolerance of brittle rupture, ductility etc.

(3) tiny crack form (when tiny crack before crystal boundary), whole mechanical property is compound greatly deteriorated.-by sample pressured state property testing crack growth.Plastic deformation is fixed in the relative narrow zone near crack tip, and wherein dislocation desity raises, and observes the very fine structure cell of generation.

(4) fully fracture when reaching its critical length, crackle occurs.

Crack nucleation under the cyclic loading results from dislocation:

-(if the dislocation of two opposite in signs endways is positioned on the plane, the distance between it is not more than about 10 dusts (1 dust=10 interacting each other ^-8Centimetre), these dislocations attract each other with the power that makes crack growth, and other dislocation is also like this, moves along same level, shift to crackle and expand crackle)

-interact with various obstacles (crystal boundary), prevent slippage and cause generating enough strong dislocation cloud.

The important stage of repeated stress failure is that crack growth is to the stage of critical size.In many cases, measure the critical size by the fracture mechanics contextual definition take millimeter or tens millimeters as unit, so that the crack length naked eyes are as seen before final fracture.In repeated stress failure, fracture is comprised of two zones: (1) fatigue cracking development part has distinguished smooth, sometimes shinny outward appearance, and surface and usually has the concentric profile in crack propagation forward position, and it also is stored in disrupt nucleus in the heart; (2) the secondth, the region of fracture that the result of the quick final fracture of conduct produces.Safe range of stress advantageously is subjected to improve simultaneously this type of structural changes (grain refining or generate flourishing structure) of the strength of materials and ductility, along the impact of the metal purity (inner centrostigma) of non-metallic inclusion.

In the situation of fatigue, the upper layer condition is even more important.The most effectively processing of residual compressive stress in hardened surface and the while induced surface layer.In the case, fatigue cracking forming core and anti-extendability improve simultaneously.Sclerosis has stoped the development of slippage, and stress prevents that surface crack is open, has alleviated the effect of an anti-component.

Be known that equally Corrosion-fatigue Strength of Steel, A.V.Ryabchenkov work (Moscow, Mashinostroeniye, 1953), it is as described below that it discloses the corrosion of metal fatigue process.At first, because dislocation desity improves, the lattice elastic distortion is accumulated at the metallic surface some parts.Subsequently, submicroscopic cracking occurs in metal inside, wherein, in disconnected a large amount of slippings of determining of separating, reach the critical position dislocation density.At last, tiny crack is grown to serve as macroscopic fracture.When this occurs, produce brittle rupture along the macroscopic fracture of the strongest development.

The absorption of surfactant, the wedging along micro chink that causes can acceleration environment be corroded.If generate hydrogen in corrosion process, it can be diffused in the metal easily.METAL EMBRITTLEMENT (in the crackle depths) in the pre-region of fracture has also accelerated damage.In plastic deformation, can accelerate the diffusion of hydrogen in along the zone, glide mirror (plane) to metal.Stop that by the hydrogen interstitial atom in the metal lattice dislocation explained the METAL EMBRITTLEMENT under hydrogen attack.

Environmental attack has sizable effect to corrosion fatigue.For example, after test, forging and aldural, the safe range of stress of D16 and V95 has reduced respectively 3-45% in water, reduced 4-5 doubly in 3% sodium chloride solution.

Corrosion fatigue in the ionogen is machinery-electrochemical process.Therefore, the electro-chemical protection such as zinc protecting sheet and anode metal coating (zinc, cadmium) is feasible.If only they are continuously, cathodic metal coating (plumbous, copper) is quite effective.This metallic surface processing also can cause the stress in the upper layer effectively.

Be known that equally Hydrogen Embrittlement of Metals, B.A.Kolachev work (Moscow, Metallurgia, 1985), it discloses the variation of the mechanical property that the suction hydrogen that is called as hydrogen embrittlement causes.With in two hours processes of the deep erosion high-performance steel 40CrSiNi of about 2000MPa, relative reduction in area is reduced to 0.63% from 47% in 15% hydrochloric acid, and elongation is reduced to 1.65 from 10.1.

In pre-deformation, the longterm strength of hydrogenation steel reduces.Therefore, for example intensity is 2000MPa, and this hydrogenation steel can stand to postpone brittle rupture under the stress of 300MPa only.Postpone brittle rupture refer to can further not carry apply static tension stress in the heavily stressed situation after a moment part or the fracture of sample.Because this breaks under the stress far below tensile strength, do not begin in the situation of visible plastic deformation having, therefore be especially dangerous.

Delay brittle rupture (it is called as hydrogen induced cracking (HIC)) has also occured in being subjected to the steel suction hydrogen process of stress.This is relevant with the embrittlement that the steel that the hydrogen concentration that its lip-deep atomic hydrogen adsorbs raising in (Rebinder effect) or the maximum three-dimensional tension stress zone causes improve.The time of ftractureing in the suction hydrogen is depended on the level of the tension stress that applies: stress is larger, and the time of cracking is shorter.The crackle that forms in High Strength Steel hydrogen induced cracking (HIC) process is the fragility characteristic, and spreads along austenite grain boundary before, and their direction is almost perpendicular to tension stress.

In metal, hydrogen can: be present in the interstitial void, form interstitial solid solution; With molecular form be present in hole, crackle and other irregular in; With compound form and impurity coexistence; And/or with compound form and solvent metal-hydride coexistence.The source of hydrogen in metal infiltration comprise initial furnace charge, wherein metal obtain with all stages of processing (melting, thermoplasticity deformation, welding, thermal treatment) in carry out technological operation environment; Electrochemical treatment is such as the metal deposition on negative electrode, acid etching etc.The metal of melting absorbs hydrogen very consumingly.At high temperature, hydrogen is absorbed (for example titanium) by many metals (even solid-state lower).Under the hydrogen embrittlement condition, ductility reduces and can change in very wide scope: almost completely lose to ductility from several per-cents.There is not unified mechanism of hydrogen embrittlement.Steel depend on many factors to the susceptibility of hydrogen embrittlement, such as strength level and condition, the Nomenclature Composition and Structure of Complexes of steel and the performance of single heating (individual heats).

The performance variation that hydrogen causes can be eliminated by hydrogen desorption from steel in slaking or the annealing process usually.But, in some cases, High Strength Steel for example, the hydrogen richness that is low to moderate 5 centimetre of 3/100 gram causes the irreversible change of remnants except dehydrogenation the time.

Hydrogen embrittlement self performance is as follows:

(1) hydrogen-type corrosion-in the carbon steel of long-term exposure under High Temperature High Pressure hydrogen environment, develop.This is based on the interaction that generates methane between hydrogen and the carbon.This reaction causes decarburization and forms the crackle that gradually infiltrates metal inside from the surface, has reduced strength and ductility.

(2) hydrogen epidemic disease-Yin from the hydrogen of metallic surface infiltration and be dissolved in oxygen the metal or the interaction between the oxide compound occurs.It is discontinuous that the gained water vapor is made microcosmic.

(3) primary blowhole-in melt or on crystalline substance is appeared, produce with molecular form precipitation Yin hydrogen.

(4) secondary hole-be derived from respect to the oversaturated Solid solution decomposition of hydrogen, and generate the fine submicroscopic porosity that is full of hydrogen.It is less than a hole, and has the shape of the sphere of being close to.

Occur in the metal of (5) reduction of shock strength and fracture toughness property-form therein hydrate.

(6) delayed fracture-destroy in advance the cracking that causes when what be in that the permanent load lower time that is lower than yield strength is generally Ductile Steel.

(7) reduction-concerning many metals, hydrogen causes creep resistance at high temperature to reduce to anti-deformation behavior.This effect has been accelerated damage under certain conditions.

(8) defective of crackle, white point, " flake "-in heavy froging, detect on the whole.

(9) bubble formation-hydrogen is penetrated into the metal and with molecular form from aqueous environment and accumulates in defective (for example non-metallic inclusion), raises with hydrogen pressure, and metallic continuity reduces gradually.

(10) corrosion cracking-in many cases, this is relevant with the atomic hydrogen that discharges in the corrosion reaction, and it is adsorbed on the crack surfaces and is dissolved in the metal, simultaneously hydrogen embrittlement aggravation.

Be known that equally Hydrogen Embrittlement of Metals (hydrogen embrittlement of metal), L.S.Moroz and B.B.Chechulin work (Moscow, Metallurgia, 1967), its type that discloses the metal hydrogen embrittlement is very various.Usually distinguish two types hydrogen embrittlement: (1) first kind embrittlement, its source changes in initial metal because hydrogen richness raises, until apply any stress, and (2) Equations of The Second Kind embrittlement, the feature that forms in metal with the hydrogen richness rising in the plastic deformation process causes.For hydrogen embrittlement many theories are arranged.A kind of theory thinks that the hydrogen embrittlement of steel is results of intergranular loss of strength under the hydrogen pressure of accumulating in and the microscopic void submicroscopic at grain boundaries.

Be known that equally Mechanical Properties of Metals (mechanical properties of metal), M.L.Bernshtein and V.A.Zaimovsky work (Moscow, Metallurgia, 1979), it discloses creep is mainly at high temperature, under some permanent load with slowly and the character of the metal of continuous mode plastic deformation.Creep by two kinds of processes that replace form-owing to cold worked reinforcing with owing to recrystallize or be lower than reduction static under the temperature of recrystallization temperature.The plastic deformation of following type occurs in creep process at high temperature the metal: slide and slippage (dislocation figure) (1), (2) twin, (3) deflection mechanism, (4) layering, (5) rotation of crystal grain and relative movement, rotation and the relative displacement of (6) mosaic block, (7) structure cell forms mechanism, (8) diffusion plasticity, and/or (9) recrystallize mechanism.

Hypothesis (move and cloud in the hole) for lattice vacancy function in the process that forms and breed at crackle extensively is accepted.

In creep process, relatively low and cause the break time when longer when stress, observe transgranular fracture.With this understanding, deformation mainly relies on crystal grain to move to accumulate, i.e. intercrystalline plasticity.In the case, the formation in hole and accumulation and final cracking should occur at grain boundaries.

The condition that forms crackle under heavily stressed and large creep is different.In the case, cause the break time reduction, dislocation-shearing mechanism (developing in crystal grain body) obtains large efficient.Aspect hole accumulation and crackle formation, the gained slip line can play and Grain-Boundary Phase effect together.

Therefore, in creep process, caused the damage of intercrystalline and the transcrystalling of metal by a kind of and identical process, i.e. the diffusion in hole, it is assembled in cloud or near hole, hole growth tiny crack, and the crack growth that finally imports owing to new hole.

Following microdefect is generally acknowledged:

(1) the shaping hole that in recrystallization process, forms and discontinuous.

(2) hole that is shaped by void coalescence.

(3) the Jog opening because producing at grain boundaries along Grain Boundary Sliding.When having the polygonization structure, in it generated, the hole is lived in concentrated communities and is indexed to dislocation was very important, does not detect hole.If this substructure is difficult to form, in wide creep temperature scope, observe hole.

(4) as the thermal activation of atomic bond fracture result's hole and tiny crack forming core.Under the physical condition that high temperature damages, all defectives mentioned above (it helps hole forming core and tiny crack development) occur to greater or lesser degree.

The result who contact as main body and mobile liquefied gas environment or the particle that carries thus, or the result who collides as solid particulate, erosion wear is present in the disengaging of solid particulate on the body surfaces on.Can enumerate the fretting wear of following type:

-in not containing the impurity with abrasive action and the current that do not have cavitation erosion, because metal and liquid and be dissolved in the interaction of oxygen wherein, because the liquid-flow of the surface film that generates at metal destroys and can denude;

-in having the air-flow of abrasive particle; This atmosphere surrounding can or cannot with this metal interaction---be respectively corrosion-mechanical shearing or mechanical shearing;

-in the jet of solid particulate.

Under volume load, the plastic deformation process is in some part localization of integral body, and wherein textural defect accumulation generates stress concentration, and the fracture origin forming core.Under surface load, plastic deformation process different (the dislocation characteristic that has kept them) is that at first the compound stress on whole contact area distributes.On the whole upper layer and on its arbitrfary point, the participation of the metal of all parts in plastic deformation in the contact area and fracture are equiprobable, cause stress dispersion.

Another feature is, in wear process, new cycle, plastic deformation and continuous crossover of the cycle of breaking occurs when following wear debris closely and be pulled away.In wear process, the structure of thin list surface layer and structure (when with outside atmosphere, high stress concentrations center and the possible temperature film forming possibility when interacting that raises).Wearing and tearing and to tear be the process that size of main body gradually changes are comprised of the separation of the spike of surface of friction and/or its permanent set.

Be known that equally Corrosion and Protection of Metals (corrosion of metal and Protection)M.A.Shluger, F.F.Azhogin and E.A.Efimov work (Moscow, Metallurgia, 1981), it discloses radioactive radiation (neutron, proton, deuteron, α-with beta particle and gamma-rays) has remarkably influenced to corrosion process, and this situation experiences in nuclear power industry.In most of the cases, ray aggravation corrosion 1.5-3 doubly.

Rapid rising that can corrosion speed under radiation.Iron, copper, zinc, nickel and plumbous atmospheric corrosion rate can improve 10 to 100 times.Catastrophic corrosion launches in uranium alloy, and it is with cracking.

In water cooled reactor, the hydrogen that discharges in the water oxidising process of uranium is diffused in the metal.In the relatively short time, crystalline structure damages because of the localized precipitation that generates uranium hydride.The hydrogen that is added to the water can spread through the protective oxide film, and interacts with uranium.The gained uranium hydride immediately with the reaction of the slower water of diffusion, generate thus more stable UO ₂The hydrogen that discharges can react with next section uranium again.Uranium and water form uranium dioxide U+2H ₂O=UO ₂+ 2H ₂Uranium and hydrogen evolution uranium hydride U+2/3H ₂=UH ₃, it generates uranium dioxide UH with the water reaction subsequently ₃+ 2H ₂O=UO ₂+ 3 _1/2H ₂

When forming protective membrane, hydrogen is diffused in the base metal, so that the time in the alloy cracking process rather than erosion rate are the most important of exosyndrome material erosion resistance.Based on testing data, radioactive radiation does not have in the basic situation about changing the corrosion process dynamics to be had considerable influence in mechanism of corrosion.The radiolysis effect comes from radiation on the water and has accelerated cathodic process.This can not observe in its surface has the metal of formation of thick oxide films.Destruction is elasticity and the thermal interaction between surface and the radiating particle, causes the defective in matallic surface layer and the oxide film.Be subjected to the phase protective film to generate the metal (for example, for aluminium alloy) of domination for its erosion resistance, this effect is dangerous.Equally, this has promoted anodic process, and erosion rate is had the most far-reaching influence.

Corrosion cracking and corrosion fatigue develop according to machinery-electrochemical mechanism: crack growth-electrochemical process, fully the avalanche type physical damage of fracture-nubbin; Do like this, the method is at the hydrogen embrittlement of crack tip with this material.Difference is the load that applies: the tension load in the Among Materials, Mechanical And Corrosive Factors During Corrosion Fatigue and the cyclic load in tired situation.Crackle type on microsection is different with the type of breaking.The hydrogen embrittlement of metal has many manifestation-take the methane that generates or corrosion cracking and thin slice (cloud of fine crack in the forging) as cost, the effect of porosity and hydride impact intensity before cracking.Hydrogen also can have disadvantageous effect to creep process, causes the too early destruction of the structure at high temperature moved under permanent load.In creep process, destructive process in most of the cases is to be caused by the crack generation institute that spreads owing to the hole and hole grows in the microfracture.

Therefore, the deteriorated method that the irreversible change of its aspect of performance is provided of material or structure causes the termination and their further security threats that uses of the function of element or structure.Because material degradation occurs and is divided into following group from all polytype destructions of various process mechanisms: local and widely hole and the substructure of corrosion failure, single or many Cracks, tiny crack, grain boundaries, the change of the mechanical wear of surface undulation and variation, generation unrelieved stress and machinery and physicals.

It causes deteriorated and has alone or in combination the working parameter of effect and can followingly divide: with outside atmosphere contact interaction, static stress, low week and high circumferential stress, interact with outside atmosphere active in nonelectrolyte or the ionogen, constant high temperature (or low temperature) or Periodical and be exposed under the radiation.The degradation mechanism that causes the above-mentioned type to damage is sorted out as follows: corrosion cracking, hydrogen embrittlement, corrosion fatigue, mechanical fatigue, chemical corrosion, galvanic corrosion, erosion, creep and Irradiation embrittlement.

All these mechanism are at different (chemical interactions between element material and the outside atmosphere in corrosion process in nature, element material dissolves at the electrochemical corrosion course Anodic, infiltration and in hydrogen embrittlement process atoms metal between the bond energy reduction of atomic hydrogen in the element material lattice, strong dislocation multiplication and generate subsequently slip band and the development of tiny crack in fatigue process, slippage, dislocation glide, form twin etc., in creep process, weakened atoms metal ionization of key etc. in the lattice in the Irradiation embrittlement process, corrosion cracking and corrosion fatigue), but something in common is weakened at the initial lattice Atom of the material of parts or structure key or disturb, and therefore deteriorated their performance.

Various preventions and to suppress deteriorated method be known.For example well known by persons skilled in the artly be Materials Degradation and Its Control by Surface Engineering (material Deteriorated and by Surface Technics control), Andrew William Batchelor work, Loh Nee Lam﹠amp; Margam Chandrasekaran (World Scientific Publishing Co., 1999, p.408, ISBN 1-86094-083-8), its disclose occur in the various forms of destructions in the representative engineering materials, and the tradition and modernity technology that is used for resisting the Surface Engineering of material degradation.If possible, by a large amount of chart diagram scientific concepts, to be convenient to as far as possible understanding.Material degradation research---for example about corrosion---is divided into independent subject to every type of material traditionally.Usually as the control of an independent subject study material degradation, such as corrosion and paint.

Be known that equally Assessment of Service Induced Microstructural Damage and Its Rejuvenation in Turbine Blades (bring out by the use in the turbine blade The assessment of Microstructure Fracture and recovery thereof), Koul, A.K.; Castillo, R. work (Metallurgical Transactions A.1988, Vol.19A, No.8, pp.2049-2066), its disclose investment cast IN738LC turbine blade its use the microstructure bring out deteriorated with creep property between related.The form of quite at length having studied is that the alligatoring of γ phase, MC carbide are degenerated, the microstructure degeneration of the disappearance of the generation of the contiguous network of crystal boundary M23C6 carbide and zig-zag crystal boundary.The result who is obtained by relational expression can show the degradation effect that use is brought out, and therefore can be used for the aptitude checking of renovation blade.The system strategy of design Ni-based high-temperature alloy hot isostatic pressing renovation circulation is disclosed.In case design renovation circulation, the degree that can analyze the microtexture renovation with relational expression immediately with reheat-process or the use of hot isostatic pressing in creep property in the turbine blade that contacts.The Zr of trace is also disclosed on the impact of the IN738LC turbine blade creep property of contact in using.

Be known that equally Repair of Air-Cooled Turbine Vanes of High-Performance Aircraft Engines-Problems and Experience, P.Brauny; M.Hammerschmidt; M.Malik work (Materials Science and Technology, 1985, Vol.1, No.9, pp.719-727), its described in operational process, stand to be out of shape, cracking, burning and material degradation by air-cooled turbine blade Ni-based and that cobalt base superalloy is made.The compound geometry of these parts and the composition of casting alloy and microtexture ununiformity have limited the selection of repair method.The selective chemical of diffusion coating is peeled off; Eliminate crackle and restoration contour profile by the combining method that comprises welding and soldering tech; And to generate coating by the diffusion carburizing treatment be the main method of using.The method can cause the defective of obvious reduction parts integrity.

Be known that equally Integrating Real Time Age Degradation Into the Structural Integrity Process is (with the deteriorated structural integrity process that is incorporated into of real-time timeliness In)Craig L.Brooks and David Simpson work (NATO RTO ' s Workshop 2 on Fatigue in the Presence of Corrosion, Corfu, Greece, 1998), it discloses in the existing design basic structure of design, manufacturing and maintenance that a kind of " degeneration working life " aspect with aircraft joins aircraft system.Adaptation to the structural integrity method is revised so that factory and user can satisfy needs, opportunity and the challenge that is called as Aging Aircraft Fleet.The economy that some aircrafts use is continuously impacted to force with safety existing system is improved.Project organization integrity method is disclosed with the effect that comprises corrosion, ultimate principle, device and the technology that continues constant stress corrosion crack and the relevant deterioration of other timeliness.In the mode that realizes interests in the complete life cycle of aircraft system a kind of feasible solution of utilizing proposing apparatus is proposed.

Be known that equally Evaluation of Degradation Degree of Metal in Gas Pipelines (assessment of metal degradation in the gas pipeline), E.E.Zorin, G.A.Lanchakov and A.I.Stepanenko work (Gas Industry, No.4,2003), it has described the progress of the quick diagnosis method of metal degree of degeneration in main pipeline.A large amount of research-on-researches are devoted to study the discrete fatigure failure of metal.But the physical method of studying the metal construction in main crack nucleation stage can't design can foretell the engineering rapid diagnosis system of also foretelling thus structural life-time based on the moment ultimate limit state of structural state performance variation reliably.

The design shell structure and under Vnsteady loads the method (it is based on the Linear Fracture Mechanics standard) of assessment time limit of service surpass at controlled load condition lower wall thickness in the situation of project of 80-100 nanometer good behaviour arranged.But most of gas pipeline system is made by the maximum 25 millimeters two-phase ferrite pearlific steel material of wall thickness.For many reasons, can not predict the ultimate limit state of moment to this class formation.Therefore, for example, in reshaping the process-cycle process, material is imposed sizable plastic deformation and the thermomechanical effect that can not control fully.The steel of a grade composition can have substantially different metallurgy.For laminating material, be difficult to find crack initiation condition in the practical structures according to the Linear Fracture Mechanics standard.

Under the changing load condition, welded technical inspection should comprise that the checked metal master accumulated damage of record (defective, foreign impurity, discontinuity) also obtains the process of anti-effective parameter simultaneously in low and average strength steel material.Under the changing load of any type, plastic hysteresis ring and cyclic creep in material in the record stress deformation coordinate.Plastic deformation in the availability modeling metal local volume of damaging, and improved the plastic hysteresis ring parameter of sealing.The energy that the area of ring equals to dissipate in the material, width equals the inelastic deformation in per cycle simultaneously.The development of local plastic deformation produces new discontinuity, therefore improves in the intrametallic damaged density of unit volume.

At total damage D _∑In, can record arbitrarily two levels: the genetic damage density D that is derived from metal quality ¹ _nWith its acquired character damage density D for the function of the genetic damage that in the metal reshaping process of manufacturing structure body, produces and operational condition thereof ² _∑The damage of the first level will be controlled the intensity of the second horizontal increment, and this is nature.

Although in the crack growth research of adopting the fracture mechanics standard, obtained considerable achievement, can't clearly describe the whole process of main crack growth.This can be interpreted as when crackle greatly to size during than large hundreds of times of the crackle of metal construction element (in the stress field in the first kind) just can use the fracture mechanics standard.For the Development Engineering fast diagnosis method, people have to example exploitation by two-phase ferrite pearlific steel material at the generation model of the defective of main crack nucleation stage certain-length.

The characteristics of real material are the combinations of the typical linear scale that links to each other with the structure (microtexture and macrostructure) of different levels.Need to consider material structure in describing deformation and breaking-down process, this is basic in fracture mechanics.According to a kind of sorting technique, what be concerned about most is the 7-10 category, namely 10 ^-5-10 ^-4The long defective of rice, the size of itself and structural element is suitable.

Necessity and adequacy principle have been put the basis as the quick diagnosis method in order, and develop this quick diagnosis method and be used in use structural part: the structured material volume of being diagnosed should be enough to reflect how reshaping and manufacturing technology, working conditions (it causes main crackle to generate) affect this material.In the case, main crackle refers to one of existing micro-crack, and it with than the faster speed development of all the other crackles, and causes the controlled damage of structural part under specified criteria.

Structural element namely can represent the crystal grain of necessary and enough volume metals, simultaneously, the physics that can instrument record by the micro-hardness measurement on the diagnosis target surface imposes the structural element of reshaping technology and load-up condition-and-variation of mechanical property.

If the sample that rigidly fixes along contour is taken as structural element, indenter pressure process represents external load, and the micro-hardness measurement structure will objectively respond damaged exist (micro-crack) in mechanical property, pressurization deformed state and the structural element.The combination of microhardness data, namely enough large data selection is complete, can characterize by the condition of diagnosis metal volume.

Because be impossible under the optical observation of the impression grain field condition, obtainable array and micro-hardness measurement spacing (for the ferrite pearlific steel material, 60-80 bar impression, 0.02 millimeter of spacing) are essential and sufficient.Load on the indenter is selected from this scope, and wherein Kirpichev-Kick-Davidenko ' s impression similarity condition is unavailable for the steel of this structure species.

In order to explain the result who obtains, proposed following model: each is processed according to the method for one of three kinds of variants from the micro-hardness measurements that unit surface obtains:

(1) indenter is absorbed in and does not have along in the structural element of the micro-crack of contour; The adjacent structural element of first row does not have destroyed yet.In the case, observe the basic microhardness value of this element.

(2) indenter is absorbed in the structural element with micro-crack, but it is present in the adjacent volume.As the structure of additional 3 D deformation, distributing again of the stress and strain that ununiformity causes in the subsequent cell volume causes being reinforced by the contact of diagnostic elements.In the case, record the microhardness value that increases with local stress and deformation the level rise.

(3) indenter is trapped in the structural element that has micro-crack on the crystal boundary.When the diamond pyramid is pressed in the crystal grain since under from the additional deformation of pressure head in given volume, the translational speed of indenter is significantly less than the speed of micro-crack development, crackle has the time of development.The volume continuity is destroyed, and microhardness reduces suddenly

When in a kind of with identical processing or the concentrated central zone of structural stress, in certain maintenance intervals, successfully measuring microhardness, the increase of the per-cent aspect of the new selection of registration " reinforcement " and " weakening " structural element.If this is not because the transcrystalline failure in the stress area of Second Type or local strain are hardened, the phase transformation that the ferrite pearlific steel material of low strength and average intensity does not almost cause the crystal grain microhardness sharply to reduce or raise." reinforcement " and " weakening " crystal grain per-cent changes the reduction value of metal aspect macroscopical failure resistance that dynamics will show the structural part in the use in the micro-hardness measurement sample on the target surface that The is diagnosed.

The mechanism of damaged forming core and development can be expressed as follows in the metal of the structural part in the use on the structure level: a) size is equivalent at most existing " succession " micro-crack of crystal grain length and the development of textural defect, the appearance of new micro-crack nuclear, the general lax development of structure; B) variation of Second Type stress field gradient nuclear is grown up (stress of balance on the crystal grain level) and the formation in new high stress concentrations zone; C) when destroy covering that crystal grain is disconnected determines, further growth, merging also are converted into micro-crack forming core (destruction) in the region of stress concentration of macrocrack from micro-crack.Damaged developmental stage can not correctly be reflected by solder alloy by using micro-indentation in the metal of structural part, because further crack growth is controlled to larger degree (working stress, welding stress etc.) by the stress field of the first kind of balance in structure.

Therefore, the integrity of microhardness data selection represents the degree of material carry load ability, namely, the essential beginning micro-hardness measurement data selection with the capacity condition of main crack growth represents with the column diagram form in the metal if be recorded under the test conditions under existing loading condiction, wherein data are along the microhardness size distribution, and the column diagram in the current use will move with respect to the data under the material initial condition subsequently.

Damage accumulation parameter k _pThe quantitative criterion of comparison microhardness calibration column diagram: k _p=K _p/ K _p°, K wherein _p, K _p° be the reduced frequency of microhardness distribution column diagram when using at present and under initial condition.Consider weighting coefficient a _j, reduced frequency is calculated by column diagram with the summation of single frequency, and this weighting coefficient can unify to consider the contribution (value) of each distance of microhardness data.

K _p=∑ a _if _jF wherein _j=n _j/ N _jThe frequency at the single interval of-microhardness data

Herein, N=∑ n _j-crystal grain sum; n _j-cause the number at the given interval of microhardness data.

Weighting coefficient a _jMethod of design based on the linear proximity of 0.1 to 1.0 distribution plan.The numbering that should keep the initial condition column diagram is calculated this weighting coefficient.

Table 5

Attention: σ _TSAnd σ _TSDispersion be 25MPa, at T _c=20 ℃ of lower shock strength KCV---0.2MJ/m ², be 0.01-0.07MJ/m being lower than under 0 ℃ of temperature.

The reduced frequency K of the micro-hardness measurement column diagram of the metal in the use _p, raise on constant basis, simultaneously the damage accumulation constant k _pAlways greater than 1 also same rising.

Selection is used for research from the controlled rolled steel pipe in Urengoi gas condensate field.The mechanical property of emergency stock pipe is compared with the mechanical property of the pipe of use after 20 years.The metal of pipe is at chemical constitution and the mechanical properties steel close to strength grade Cr65.The metallurgical analysis of the sample that downcuts from the tube portion that used 20 years shows, this metal does not have the crackle that can detect by method of non-destructive examination.

As shown in Figure 5, in the shock test process of the controlled rolled iron sample behind the inherent life-time service of wide temperature range (+20 to-75 ℃), consume in main crackle from aspect the energy of groove forming core with aspect distribution energy that emergency stock pipe sample performance is compared, failure resistance significantly reduces.After using over a long time, the strength property (yield strength and tensile strength) of crack pipe metal improves slightly, and plasticity-and ductile performance (elongation and shock strength) reduce simultaneously.Should be noted that the pipe metallicity is anisotropic along rolling direction with vertical rolling direction.In the material behind life-time service, the change rate of all mechanical propertys of vertical rolling direction is greater than the change rate along rolling direction.

Figure 12 shows the thoroughness that the surface microhardness measurement of the pipe after 20 years for part emergency stock pipe and use is selected.Use after 20 years, the microhardness array of data to the left, lower data one side shifting.This shows the badly damaged of pipe metal.Quantitatively, the variation of the integrity of the microhardness data selection that obtains of the tube portion surface behind life-time service can be passed through the damage accumulation coefficient k _p=3.604 characterize.

Note, under accumulation service failure condition, only just observe this type of substantive microhardness to lower data one side shifting in controlled rolling stock, these are for other tested steel of this structure type and be not true to type ( steel 3,20,10,09Mn2Si).Latter's (and welding joint) can be by selecting this sign of more uniform variation in the integrity, that is, damage accumulation increases when accompanying by the percentage ratio of undesired height in the selection and undesired low microhardness data; The only in the end stage growth of recording undesired low data.This can be owing to the manufacturing technology that is used for the controlled rolling steel.Early to the sheet material manufacturing stage, metal carrier body imposes real remaining plastic deformation.Realize that under astable condition the plastic hysteresis ring requires that metal carrier body is imposed contacting strain and is hardened to and keeps out this micro-crack development.If the deformability of material volume is used up, be possible in the stress relaxation of progressive crack tip, crackle interrupts it and continuously growth, accumulation potential energy.Test is lower to be obtained in the processing of selection integrity of microhardness data at target surface, is not having in the situation of strain hardening under life-time service load, records the generally lax process of controlled rolling stock.

Can from research, reach a conclusion, the target surface that can be diagnosed in structure processing and service stress centrostigma zone is measured microhardness, in order to estimate the metal degradation, and set up incidence relation between the tolerance performance that in microhardness data selection integrity and macroscopic view damage forming core and structure, develops.

Be known that equally Effects of Mixed Metal Addition on Surface Film and Corrosion.Prevention of Stainless Steel in BWR Water, Takeshi Sakai, Yoshiyuki Saitoh, Yuuji Midorikawa and Teruchika Kikuchi work (9 ^ThInternational Conference on Environmental Degradation of Materials in Nuclear Power Systems-Water Reactors, 1999), it provides in a water reactor and uses the result that hybrid metal is dosed.As the replacement technology that zinc is injected BWR water, hybrid metal is dosed and is developed.Hybrid metal is dosed compound and a small amount of natural zinc that uses manganese, nickel, magnesium.Zinc concentration is reduced to the tolerable limit that can not improve activation Zn-64 radiation accumulation, namely according to the reactor water analysis result at Onagawa-1, be lower than 1ppb, and the synergistic effect that the hybrid metal element is reduced in corrosion on the stainless steel surface and radiation accumulation is expected.In present research, carry out high temperature and high pressure kettle and test to study the effect that hybrid metal is dosed the corrosion in the BWR environment of simulation to sull feature and stainless steel.The result shows that it can be the replacement technology that zinc injects separately that hybrid metal is dosed.

Be known that equally Microstructure and Evolution of Mechanically-Induced Ultrafine Grain in Surface Layer of Al-Alloy Subjected to USSP (stands the ultra-fine of mechanical induction in the upper layer of Al-alloy of USSP The microstructure of crystal grain and evolution)X.Wu, N.Tao, Y.Hong, B.Xu, J.Lu, K.Lu. work (Acta Materialia; 2002; No.50; the 2075-2084 page or leaf). its provide with high definition transmission electron microscope research by ultra-fine grain (UFG) microstructure in aluminium alloy 7075 upper layers of the fierce forging of ultrasonic shot peening (USSP) with the understanding Microstructure evolution with form the result of relevant Grain Refinement Mechanisms with structure.

Ultra-fine grain (UFG) material has attracting science importance.Be characterised in that very thin grain-size (nano level or submicron order) and a large amount of crystal boundary area (and volume) on these material structures.The UFG material has uncommon and outstanding machinery and physicals, and it fundamentally is different from, and usually is far superior to traditional coarse granular polycrystalline analogue.Large plastic deformation (SPD) is a kind of effective working method, is used for making various UFG structural parts by applying by force strong plastix strain to metal and alloy.By SPD make the UFG material can obtain to be higher than other technology (for example inert-gas condensation method, high-energy ball milling and skimming wear), two significant advantages.At first, can make bulk sample.The second, these samples do not contain hole and the pollutent of any remnants.The gained microtexture of introducing by SPD is grain refining basically, and is accompanied by high internal stress and high energy Non-equilibrium Grain Boundary.Several technology can be used for making other the essential high-ductility strain of hundreds of per-cent level now, comprise Equal-channel Angular Pressing (ECAP), high pressure torsion method (HPT), multiway forging method, three axial deformation and alternating bending aligning (RCS).

The understanding that is included in the Microstructure Development among the SPD is the essential problem with research topic of the very big importance of theory and technology angle.This mechanism should not only be explained grain refining, can also explain the high angle crystal boundary that generates the strain with raising.Research before is verified, and is the most remarkable in the refinement of process initial period grain-size in repeating deformation process, for example low and medium strain, and when further strain, keep substantially constant.But under large strain, the crystal boundary azimuth zeroset accounts for space of top prominence.Being exposed to textured surface under the random and multi-direction deformation can effectively improve the low angle grain boundary azimuth zeroset and develop into high angle crystal boundary azimuth zeroset.Nearest research has been reported and slip system and the relevant grain refining that interacts thereof.By in the ECAP process operation multiple slip be to make the ultra-fine dislocation born of the same parents that sealed by plane.In the RCS process, generate ultra-fine subgrain by dislocation along the slipping plane superimposition.But up to the present the basic mechanism of grain refining itself also do not have any progress in the SPD process.Even the variation of microtexture and mechanical property has been described in great majority research, they can not disclose the microtexture response to the dynamic plasticity strain, therefore, can not illustrate the UFG structure to the relation of plastix strain.

The principle of USSP technology is as follows.The high-energy ultrasonic wave producer vibration reflection room of high frequency (20kHz), the wherein stainless steel bullet of 7.5 mm dias resonance.Bullet applies repetition, at a high speed and multidirectional impact at material surface immediately.As a result, give the surface violent strain by contact load.Be based upon simultaneously the upper surface place and go deep into matrix to peaked strain gradient from 0.The details of equipment in document before, have been reported.In this research, at room temperature carry out in a vacuum USSP and processed 15 minutes.

Study on Microstructure has disclosed the USSP method can introduce the UFG structure in the bill of material surface layer.Because the increase of stress on whole deformation layer, distance layer end face is nearer, and grain-size is more tiny.The grain-size that has three kinds of levels: (1) has inner parallel, the little band (MBs) (the first level) that extends that elongates subgrain and structure cell fault block (CBs); (2) structure axle, the sub-micro granulation (the second level) such as, and axles such as (3), Nanoparticulated structure (the 3rd level).When near end face, thinner, more isometry, more directed mistake and more even distribution that crystal grain seems.

In polycrystalline material, dislocation glide, accumulation, interaction, entanglement and space are reset and are caused the crystal grain segmentation in order to plastix strain is provided in deformation process.

USSP can provide high-strain-rate high strain to upper layer repeatedly.Large plastix strain can be made highdensity dislocation, and it is being effectively when blocking slippage under strain that improves, and the result is subdivided into original grain the subgrain with the dislocation that forms at they crystal boundaries for the mechanism response meeting of supplying with a large amount of plastix strains.Crystal grain is subdivided on the macroscopic scale and occurs, and generates MBs under low strain.Along with further strain, subgrain can further be broken for less CBs.Under larger strain, can make sub-micro-and nanometer-size subgrain.

By repeatedly carrying out USSP, can realize very high strain.Notice that highdensity dislocation usually is present in the deformation texture of various grain-sizes.Simultaneously, produce low angle grain boundary, it means the new crystal boundary of continuous generation in deformation process.Along with the strain that improves, with more and more finer scale generation microsegmentatioin.As a result, the process of structure refinement can successfully proceed to sub-micro and nanometer state.

Multi-direction shot peening can cause even greatly be different from the deformation that other SPD method causes in the variation of the slip system with strain paths of identical subgrain inside.Dislocation not only with existing active slip system in other dislocation interact, also with before deformation in the non-active site misphase mutual effect that produces.This can promote the generation of subgrain.The result has improved the efficient of grain refining.

Development Deng the crystal grain of axle, high orientation mistake is comprised of two steps,, generates subgrain by crystal grain segmentation and directed wrong differentiation of crystal boundary subsequently that is.But the subgrain that the crystal grain segmentation obtains has critical size before stable, and its strain with certain value is relevant.The crystal grain segmentation can be continuous definitely, and final, and after the deformation of specified rate, strain again can not reduce the size of subgrain continuously.In this stage, because dislocation moving is subject to tighter restriction, the slip system in the adjacent subgrain is activated the corresponding strain that applies, in order to these subgrains are rotated to the more favourable orientation of energy.Shot-peening provides multi-direction strain approach and high strain rate, and this is especially effective when promoting the subgrain rotation.The mechanism of high directed wrong development should be the subgrain rotation.Therefore, the accumulation of subgrain rotation obviously is as further deformation being provided, obtaining the primary mechanism of method of the equi-axed crystal of high orientation mistake.

By activating the deformation of slip system control subgrain, wherein reached critical resolved shear stress.In the plastix strain process, can in each independent subgrain, activate different slip system combinations.Because directed different, adjacent directed wrong subgrain will have different activation slip systems.Some slip system with Selective activation with the interior energy in the reduce subgrain.Adjacent directed wrong subgrain will rotate to unanimously, so that reduce crosses the energy of subgrain boundary under the motivating force of the slip system of Selective activation.Along with strain improves, the dislocation glide subgrain is no longer by providing deformation along identical sliding system, and therefore begins independent rotation.Angle of rotation increases, and finally is called the crystal grain of high orientation mistake.When comparing with other SPD treatment process, USSP produces high strain rate, plays an important role in its lattice rotation in deformation process.With respect to low strain rate, for the strain increment that equates, high strain rate causes obviously higher stress of fluidity.Computer simulation has disclosed, because the plasticity automatic rotary component that reduces and a large amount of activation slip systems, the strain rate that plasticity is higher promotes the lattice rotation to comparing the higher degree of low strain rate in simple shear.Observe, the average orientation mistake angle between the subgrain improves for identical strain, simultaneously in the fine aluminium drawing process strain rate from 6 * 10 ^-6Bring up to 6 * 10 ^-1s ^-1

Therefore, USSP provides the simple and effective method of making the UFG structure at aluminium alloy 7075 upper layers.In the USSP process microtexture development be characterised in that little band (MBs) of elongation with dislocation born of the same parents' (DCs) sequence, respectively have raising strain etc. axle sub-micro and nanocrystal.Grain refining and Microstructure evolution are as follows in the USSP process.In the plastix strain process, generate subgrain so that strain to be provided through the crystal grain segmentation.For further deformation is provided, generate the crystal boundary of high orientation mistake by the subgrain rotation.

Be known that equally The Effect of Controlled Shot Peening and Laser Shock Peening on the Fatigue Performance of 2024-T351 Aluminium (controlled shot peening sclerosis and laser shock peening are to the fatigue property of 2024-T351 aluminium alloy for Alloy Impact)CA.Rodopoulos, J.S.Romero, S.A.Curtis, E.R.de los Rios, P.Peyre work (Journal of Materials Engineering and Performance, 2003,12 (4), pp.414-419), it discloses shot peening, laser shock peening and dual (bullet and laser peening) processing impact on the fatigue behaviour of 2024-T351.Test shows, improves lower fatigue lifetime in all three kinds of situations, and laser shock peening and Duplex treatment show the fatigue property more superior than shot peening.The fractography analysis shows that loss in ductility causes the performance of shot peening relatively relatively poor.

The potential of adopts surface engineering technology, processes (CSP) and laser shock peening such as controlled shot peening and processes (LSP) and understood by automobile and the worker's industry of navigating already with the potentiality of the resistance to fatigue of improving whole block material.The beneficial effect that is brought by CSP and LSP mainly comes from and is generating stable compressive residual stress and strain hardening near surf zone.In the situation of high-strength material, compressive residual stress is even more important among both.But in softer material, because the partially or completely relaxation of unrelieved stress can occur, strain hardening will be preponderated.Reported that strain hardening has delayed the growth of micro-crack, but accelerated the long crack expansion that low remaining ductility causes.But in high-strength material, by subsurface crack growth (usually in the zone of stretching unrelieved stress balance compression residual stress field), the beneficial effect of compressive residual stress can be traded off.In smooth tired parts or therein the surface is caused and is not considered in the element of critical nuclei point, subsurface crackle even can be harmful to.Surface roughing is the main deleterious effect of CSP.Because of the part thickening of source far away stress, surperficial roughing can illustrate too early appearance and the growth of short fatigue cracking.

The latter shows, the application surface engineering beats around the bush to improve resistance to fatigue, and it can be Surface Engineering even have the situation of counter productive wherein.For condition (CSP and LSP can produce useful result under this condition) is set definitely, set about carrying out the research of these surface treatments aspect the resistance to fatigue of 2024-T351 aluminium alloy.

Using the Tealgate shotblasting machine to carry out controlled shot peening processes.Shot peening strength is 4A, and this can adopt the spherical cast steel ball of S110 (0.279 millimeter of diameter, hardness 410.5-548.5Hv), input angle 45 to spend and 200% fraction of coverage realizes.The surfaceness of when maximum, the near surface of research, unrelieved stress, recommending these conditions to improve with balance.

In water-lute, be used in the Continuum YAG laser apparatus (Powerlite plus) that moves under green wavelength (0.532 micron) condition and carry out laser shock peening.About 1.3 Jiao of output energy, the pulse duration is 6-7 nanosecond.All samples are protected by 70 microns aluminum coating, not affected by the heat effect of LSP.Laser intensity is set as 10GW/cm ²(predictable pressure 5GPa), focus is 2 millimeters.Duplication with 50% is processed sample (1 time=4 times local pulse), and fills with 2 to 3 times.

The result shows, two kinds of LSP and Duplex treatment can be independent of their original surface polishing and significantly improve fatigue lifetime of material.Process poor performance but Duplex treatment shows with single LSP, it has confirmed the discovery about low remaining ductility.Just really improve when only comparing with the EDM polishing owing to the life-span of CSP on the other hand.Compare with mirror polish, CSP seems not have effect in fatigue lifetime.The not best performance of CSP is when similar 5M cycle mark even more noticeable.Explain this achievement with the theoretical analysis that proposes.According to this work, the part unrelieved stress is used for the roughening (nominal stress of expansion) that improve on the balance surface.Process and corresponding K for selected CSP _t, think that for the stress level of the 200-300MPa that applies, the balance unrelieved stress in first 50 micrometer depth is 90-125MPa.Show that more than the rest part of unrelieved stress should make improve fatigue lifetime.

In order to help to explain testing data, carry out widely fractography analysis.Check fracture surface with Camscan Mark 2SEM.Before inspection, surface ultrasonic cleaning in pure based sols.Figure 13-18 has shown crack nucleation site and the infant cracking growth of all six groups tests under the maximum stress of 300MPa.

More particularly, Figure 13 has shown surface crack cracking and the crack growth with bright finished early stage material.The microphotograph of fractograph clearly illustrates that the growth (shear mode growth) of facet.Figure 14 shows surface crack cracking and the crack growth of the early stage material with EDM polishing.Nearly surf zone shows the sign of multiple cracks nuclear, may cause because of irregular surface.Figure 15 shows chink cracking and the crack growth form of S110-200%-45 ° of CSP sample.The has facet area to expand to about 150 microns degree of depth.Have facet area be split the shape repeated stress failure around.Figure 16 shows LSP 10GW/cm ²Crack initiation and the crack growth of (2 times).The microphotograph of fractograph shows the surface crack cracking, and crackle is in 50 microns branches.The travel path of crackle B almost is parallel to the direction of stress.Figure 17 shows LSP 10GW/cm ²Crack initiation and the crack growth of (3 times).The microphotograph of fractograph shows the surface crack cracking, and crackle is in 90 microns branches.The travel path of crackle A almost is parallel to the direction of stress.Figure 18 shows the crack initiation from typical shot peening indenture.Crackle branch also clearly.

In having the sample of mirror-like polishing, lack surface stress concentration degree feature and cause single crackle nuclear (may at an inclusion place), and cause being close to semiorbicular surface cracking (referring to Figure 13).On the other hand, the uneven surface of EDM polishing has promoted multiple cracks forming core site, and it links to each other in early days, and crackle adopts the half elliptic (referring to Figure 14) that elongates.The fracture surface of 4A CSP shows the restricted crack growth that facet is arranged, and the extensively tired growth of visible splitting shape, and this can be interpreted as the chink of faster growth.More than strengthened initial loss in ductility supposition.The very high and irregular dislocation desity that loss in ductility can cause because of work hardening owing to nearly surf zone.In the situation of LSP, fracture surface shows the bifurcated of crackle.In both cases (2 times or 3 times), a part of crackle are observed and almost are parallel to the stress direction propagation, and show slow crack growth speed.Crack path understands the tendency that " parallel " crackle is propagated along the Minimum Residual residue stress with the sealing look-up table of corresponding unrelieved stress.On the other hand, " vertical " crackle shows the facet that has of increment and grows, especially in twice situation.Duplex treatment demonstrates the indications of fracture closer to LSP (crackle branch).Opposite with CSP, Duplex treatment does not demonstrate the sign of splitting shape fracture.

Because CSP and Duplex treatment provide the sclerosis of nearly upper layer, and only CSP shows the sign of loss in ductility, supposes in the situation of Duplex treatment, by possible the rearranging of nearly surface dislocation, and the possible loss in ductility of unrelieved stress compensation that LSP produces.This means that owing to the part relaxation of unrelieved stress, the fatigue property of CSP material is not good to be possible.In this article, be important to note that unrelieved stress relaxation Time-Dependent and stress level.Therefore, can obtain better to understand by unrelieved stress relaxation figure being contacted crack length.

Fatigue data shows that even all processing (CSP, LSP and Duplex treatment) have all improved fatigue lifetime, LSP and Duplex treatment have the superior performance that is far away.Fractography the analysis showed that this is owing to GSP but not the loss in ductility phenomenon that the sample that LSP and Duplex treatment are crossed stands and possible unrelieved stress relaxation.

In a word, can draw following results:

(1) CSP, LSP and Duplex treatment are estimated to reduce production costs thus the fatigue lifetime can improve the not good parts of mechanical workout;

(2) as in CSP and the Duplex treatment, find that LSP causes negligible strain hardening;

(3) LSP and Duplex treatment show more than the more superior fatigue of CSP and improve;

(4) loss in ductility owing to strain hardening and possible residual mechanical stress relaxation in CSP, may occur, and need further research; With

(5) this material of prestress (Duplex treatment) can improve the magnitude of unrelieved stress, and this unrelieved stress of Simultaneous Stabilization.

Be known that equally Basic Metallurgy, G.A.Kashenko work (Moscow, Mashgiz, 1957), its crystal form that discloses metal is by arranging with known distance each other and determining by the ion of unbound electron bonding.Atom site represents so-called lattice point.Arrange point and can form various geometric profiles, the lattice with particular configuration is provided.The space that each lattice occupies can difference and the lattice volume can be large arbitrarily.In order to characterize lattice, its least part can be only with the form of explanation of unit profile, and this unit profile consists of whole lattice when copying.This minimum lattice is known as unit cell or structure cell, and it defines the type of each lattice usually.

For crystal, following crystal system is set up according to the slope of coordinate axis and the relative length of parameter: cubes, tetrahedron, orthorhombic, oblique crystal etc.Aluminium for example has face-centered cubic lattice (metal with this lattice types is very easy to plastic deformation usually), and iron has face-centered cubic lattice and body centered structure.Cubic(al)grating is characterised in that all angles between the axle are 90 °, and all parameters are identical.Polyhedral representative profiles is cubes.The variant of cubic system comprises space center (or body-centered) lattice, and the difference of itself and simple cubic lattice is that as shown in Figure 19 and 20, except the atom on cube-corner, it has an atom at the cubes center; Also comprise face-centred lattice, it has each angle of being positioned at all cubic planes and the atom at center as shown in Figure 21 and 22, namely be rendered as the cubes with face placed in the middle.In addition, Figure 19 and 20 has shown respectively the body centered lattice of form crystal lattice and structure cell form.Figure 21 and 22 has shown respectively the face-centred lattice of form crystal lattice and structure cell form.

Therefore, each metallic element is xln or crystal.How much regularities of particle alignment are given its some characteristics so that it is from noncrystalline or amorphous body is different in the xln.At first, anisotropy or vector property (vectoriality) refer to the nature difference according to direction.Another feature of xln is to have slip plane or rift, particle under the mechanical effect that crystal is applied along its slippage or peel off.This breaks crystal (if fragility) into pieces or makes its deformation, and namely nondestructive ground changes outer form.

In the first situation, the fracture of metalwork has clear surface, along this surface, and crystal, easier fracture.This class surface is known as the rift face as shown in Figure 23-25.When occur not losing efficacy and crystal only during deformation, this is caused by the slippage of particle along slip plane.

Metal crystallization from liquid begins when crossing it cold and can obtain nucleus of crystal all the time.This causes dissimilar crystallizations to form.Under some exceptions, may form full weight or the full section crystal of geometrical rule.But this needs some favourable condition.Therefore usually, crystal is made of irregular outer shape and is known as crystallite.

Crystal with two types.In one case, more or less present circle near the outer shape of polyhedral how much regularities.This crystalloid is known as crystal grain or particle.In another case, crystallized form has with the form of bifurcation of packing space not, and is known as dendrite, and it presents the first phase of formed crystal usually.

Any metal all is the polycrystal that comprises many crystal grain.Adjacent crystal grain has directed different lattices.Crystal boundary is known as the high angle border, because the crystallization direction in the adjacent crystal grain forms the angle of maximum tens of degree.

Each crystal grain is made of the independent subgrain that forms so-called substructure.Substructure is relative to each other with the angular deflection directed (off-oriented) from minute counting to several units number of degrees.Subgrain is measured as the 0.1-1 micron, and it is less by 1/3 than crystal grain.Independently the border between the crystal (crystal grain) is generally the transitional region of the maximum 2-3 interatomic distances of width.Atom in this zone and differently arrangement in crystal grain body.In addition, impurity is tending towards being enriched in the grain boundaries of technology metal, and this principle of further upsetting rule is arranged.Observe smaller upset at the subgrain boundary place.Dislocation desity in the metal improves with the raising of subgrain crystal orientation drift rate and the reduction of subgrain granularity.

Grain fineness number remarkably influenced metalline.Large crystal grain mainly is accompanied by lower metal mechanical quality.In addition, other character may change, and this can be interpreted as the extension more or less of intercrystalline boundary.In general, crystal boundary at first shows as the impact of metalline, and these crystal boundaries are the surfaces of separating crystal grain, and wherein the particle of metal itself (atom) is different from the atom of the lattice that is arranged in crystal grain aspect energy.Intercrystalline particle is considered to have higher-energy, the surface energy that plays an important role in the phenomenon that for example occurs in comprising the various objects of metal and alloy thereof.Therefore, the interlayer of the intergranule of the atomic form of random arrangement (it is regarded as the amorphous metal film sometimes) may affect the character of whole metalwork as a whole.

But except this class film that is made of atoms metal itself, metal used in the practice has impurity all the time, and it also may be arranged in intercrystalline space and affect metalline with film or inclusion form.For example, if this class film is weak (fragility), the key of intergranule can be weakened, and metal can rupture under the mechanical effect of grain boundaries.In this case, observe the transgranular fracture of metal.Occur if break in the crystal grain, then intracrystalline failure can occur.

Structural changes in the open solid metal of the below.Can only in standing allotropic change metal, obtain close grain with hot form (by only in solid-state middle heating and cooling) by coarse grain.This class changes the transformation that consists of from a kind of lattice to another lattice, i.e. atomic rearrangement from a position to the another location.Each lattice types is allotropic modification or the modification of metal, and this is commonly referred to as phase, and is known as the polymorphic metal with the metal that several variations exist.Each modification have its oneself temperature province---it is stable in this zone, therefore under some temperature, should be transitioned into another kind from a kind of modification.Thus, be known as the crystallisation process of secondary crystal, they are different from the primary crystallization that occurs in the liquid curing process.

The polymorphic metal comprises iron.In iron, between solidification point (1540 ℃) and ordinary temp, exist several allotropic change.Modal in the practice is variation under 910 ℃, and it causes the γ modification to be transformed into α modification (vice versa in heat-processed) in process of cooling.The essence of this variation is, the atomic rearrangement that consists of cubical γ with face placed in the middle-iron lattice becomes cubic(al)grating placed in the middle, and this is the typical case of α-iron.This variation of internal structure is accompanied by the variation of the outer shape of crystal grain crystal, and recrystallize namely occurs.In recrystallize, grain fineness number significantly reduces.New crystal is closely adjacent each other, has improved metal strength.

Therefore, by utilizing allotropic change in the metal, can bring out recrystallize and obtain close grain by coarse grain.Coarse grain cast iron is presented among Figure 26-27 to an example of this microstructure change of compact grained thermal treatment or annealing iron.More particularly, Figure 26 has shown the microstructure (* 20) of cast iron, and Figure 27 has shown the microstructure (* 100) of annealing iron.

If (for example in aluminium) does not occur allotropic changely in metal, crystal grain is (only thermal treatment) refinement in the above described manner.In this case, unique method is mechanical-moulded in advance, and it brings out the so-called plastic deformation of metal.After this, can obtain by heating the crystal grain of various size.

The method can only be used for tough metal, namely can bear those of mechanical effect and its outer shape of change (deformation) in situation about not losing efficacy.Metal can be mechanical-moulded by the whole bag of tricks, comprises rolling, stretching, forging, pressure forming etc.Every kind of situation has some distinctive metal proterties according to the method that applies; But in all cases, the main process of generation is the plastic deformation of metal, and it comprises the outer shape that changes metal and does not lose integrity and intensity.

Raising and ductility (being the ability of further deformation) that Metal Deformation is accompanied by its intensity reduce.The intensity of metal hardness and raising is improved simultaneously.In practice, metal becomes " rigidity ".Because this state of the metal that deformation obtains is commonly referred to as the cold-working industry.Cold-working industry state is mainly brought out by displacement or the slippage of lattice particle in to the mechanical effect process of the crystal grain crystal in the metal.

The deformation of metal begins from the slippage under power (when above-mentioned slip plane was located more easily with respect to this power, this power was less) effect along the easiest slip plane (atom these faces is very tight each other) usually.Similarly slippage is illustrated schematically among Figure 28-30 i.e. slippage in monocrystalline zinc in the stretching of monocrystalline circular specimen.The stretching of sample is thin metal layer (also can be known as thin metal part or thin metal block) multiple slip relative to each other.More particularly, Figure 28 has shown the zinc monocrystalline (basis (cross section)) of hexagonal prism form.This face is the easiest slip plane, and Figure 29 and 30 has shown the particle piece in the crystal samples of slippage in the direction.

With the slippage while, thin metal block changes its direction relative with tension force gradually, and its plane is tending towards turning to for slippage inconvenient, namely has the position of maximum skid resistance.Therefore, along with crystal deformation, further the required stress of deformation improves.Except the easiest slip plane rotates to disadvantageous position, the stress that improves in the metal in the slipping may by with slip locations near more relevant other factorses of off side (the forming of lattice distortion, face warpage, capillary segment, space etc.) of particle cause.

Therefore, reach certain value along the skid resistance of easy slip plane, wherein slippage stops and beginning along different directions or secondary slip plane (it is inconvenient for slippage and favourable direction).Along these quadratic powers to slippage do not reach large degree as in the situation of first slippage, and under the stress that obviously improves, occur, until the latter causes the separated from one another of glide lamella, this may cause sample to lose efficacy.

Therefore, only in an esoteric simple slippage of crystalline substance (translation), namely the relative displacement on the plane of independent piece could be explained the essence of the variation that wherein occurs and cause cold-working industry state in plastic deformation in the crystal.In reality, even in a crystal, deformation also is not limited only to simple slippage (translation); When grain colony not only also rotates a certain angle along planar slip, dibit also may occur move.Therefore, in deformation, the structural changes very complex in crystal grain crystal only.

When multiple grain (polycrystalline) metal (being rendered as a plurality of closely adjacent crystal grain) deformation, it is more complicated that the method becomes.Usually this adjacency that has the crystal grain of various orientations (direction) should naturally hinder the free slippage in each crystal grain and allegedly prevent deformation.Usually the intergranular material in grain boundaries appearance and the slippage of obstruction piece can have same function.

But, although exist this class to suppress, slippage still in crystal grain, occur and each crystal grain elongation (or in compression, flattening) and by main in one direction directed and consist of before a plurality of slide blocks of " fragment " of full die consist of.

In fact, the structure inspection of deformation metal has shown similar elongated grain.Figure 31 has shown the microstructure (* 100) of Deformed Iron, and Figure 32 has shown the microstructure (* 300) of undeformed iron.In strong deformation process, crystal grain becomes so long so that they are being the reasons that this class formation of deformation metal is known as fiber as fiber and this more in shape.Therefore, " fiber " in this structure is identical original metal crystal grain, only has the structure and the lattice distortion that change owing to slippage.Therefore still there is not grain refining.This structure does not have obvious independent close grain, and the elongation border of (initially) crystal grain before only having as seen.Under low deformation degree, this structure may from original texture almost do not have different because crystal grain elongation is little and crystal boundary is not destroyed.In this case, the structure indication of ongoing plastic deformation is the slip line that occurs with the parallel or interlacing line form that distributes at whole crystal grain tangent plane on the deformation metallographic tangent plane of metal.The example of the slip line on the not etch gold phase tangent plane of iron is presented among Figure 33.

Under deformed state, this is not to stablize very much on thermodynamics substantially not have crystal grain and this state, has excessive free energy.For most metals at low temperatures, this unsteady state of cold-working industry metal can remain unchanged for a long time.But this should pine for becoming gradually more stable state adding, and this is the situation in the reality.

Under known temperature, in deformation crystal grain, produce the new crystal grain with undeformed (not distorting) lattice.In doing so, crystallisation process occurs again, this is known as recrystallize.The beginning of this process, the temperature when namely beginning to occur having the new close grain of distorted lattice not is known as recrystallized threshold or recrystallization temperature.For various pure metal, this temperature different and can with metal melting temperature approximate test relatively.Absolute recrystallization temperature has been indicated as about 0.4 of absolute melt temperature.In crystallisation process, grain fineness number changes so clearly so that can measure mean grain size and can schematically show grain growing according to various factors.The recrystallize figure that draws in the space can represent the relation between grain fineness number and two factors (such as Heating temperature and in advance deformation degree).Therefore, mechanical treatment (deformation) and heating subsequently (recrystallize) can make grain refining in any toughness coarse grained metal, and recrystallize figure helps the crystal grain of accurately considering principal element and obtaining desired size and therefore obtains various metallines.

Metal can pass through the whole bag of tricks, for example ball and roller polishing, shot peening, laser-enhanced and the plastic deformation of high strength supersonic method.The below characterizes some in these methods.In addition, discussed and the effect of plastic deformation on accompanying such as the impact of the structure of the metal of aluminium alloy and steel and so on.

Be known that equally Aluminum Alloys:Structure and Properties (aluminium alloy: Structure and character), L.F.Mondolfo work (Butterworths, London, 1976), it discloses the basic characteristic of aluminium alloy vs. steel.These two kinds of metals all are complex alloys.Behind melt cooling, they may have different structures according to condition (temperature, rate of cooling).Impurity in the alloy has increased complicacy.They mainly are deposited in the crystallite boundary of foundation structure simultaneously with various thin chemical species.The difference of Al-Cu alloy (duralumin) is, under the proportion that approaches with conventional aluminum, its intensity and hardness are not less than mild steel (at most about 45-50kg/mm ²σ _TSWith maximum 130H _B), and elongation δ is about 20%.If consideration specific tenacity, the i.e. intensity (σ relevant with unit weight _TS), this is almost three times of mild steel.But this intensity in the hard steel may only obtain after suitable thermal treatment-sclerosis and timeliness (mainly being artificial).Point out that after just quench (from 500 ℃), alloy has hardness, tensile strength and the elastic limit (H of reduction _B～80; σ _TS～32kg/mm ²σ _EL-11kg/mm ²).

In the heat-processed before quenching, CuAl ₂Compound dissolution, phase S (Al ₂Mg Cu).At room temperature, the copper dissolution degree is 0.2%, is 5.7% under 548 ℃.In rapid process of cooling, oversaturated sosoloid solidifies.After a while, following situations occuring: begins to form Guinier-Preston zone (high density copper zone); Throw out is reunited; Do not interrupt with the combination of lattice; (thickness is several atomic shells, and length is thin thin layer plate-like form to occur

).This causes the elastic distortion of lattice and the raising of intensity, hardness and yield strength.

The structure of aging alloy is made of αsolidsolution and insoluble iron and manganic compound.1400 hours consuming time of natural aging and more of a specified duration.Therefore, the artificial aging of use under 150-170 ℃.

Although there is quite high mechanical characteristics, the duralumin material (is worked as CuAl with low erosion resistance-Yi spot corrosion, intergranular corrosion ₂When grain boundaries precipitates), corrosion cracking, corrosion fatigue and crevice corrosion be feature.

Be known that equally The Effect of High-intensity Ultrasound on Metal Interphase (high strength supersonic is on the impact of phase in the middle of the metal), the 4th chapter, A.I.Manokhin are edited (Moscow, Nauka, 1986), and its ultrasonic surface that discloses metal strengthens based on the physical phenomenon such as alternate motion and atomic diffusion.The kinetics of this class phenomenon be complicated and usually by the distribution of lattice imperfection (such as dislocation, hole and interstitial atom) and with determine with the interactional character of impurity atoms each other.Because the dislocation structure that the dislocation structure that supersound process (1-100Hz) forms forms when the plastic deformation that is different from nature at constant sign.This dislocation structure mainly is to have the closely cell configuration of the subgrain of wall.

Under study for action, by direct contact or directly with vibrator or via the metal centrostigma, sample is applied ultrasonic energy.

In the cycle loading procedure, in aluminium, observe a large amount of dislocation loops.Through hint, by the enclosed voids dish, form ring.In the deformation process of constant sign, observe dislocation loop, but quantity is obviously less.Supersound process under the 20kHz frequency improves 1-2 magnitude with the dislocation desity in the aluminium monocrystalline.When this situation occurs, observe the crystalline-granular texture of abundant formation.Subgrain boundary is extended in orientation of oscillation, and the mean sizes of subgrain is 2 * 10 microns.

Use paper tinsel by the dislocation structure of the firm 1Cr8Ni9Ti of scanning electron microscope research austenite.After 20 ℃ of lower relatively supersound process and stretching and plastic deformation that compression causes after dislocation structure.Stretching and compressing in the sample, dislocation is more level and smooth, and the sample of supersound process has dislocation and a large amount of threshold value (thresholds) of more distortion and tangles.The intersection of this proof under ultrasonication, laterally slide and dislocation climb.Along with temperature raises, the number of die with high bit dislocation density improves, and has the trend that forms cell configuration, a large amount of dislocation joints (jogs) and tangle.Digital proof, crystal boundary and carbide precipitation thing are the dislocation sources.

Except dislocation rearrangement, the ultrasonic atomic diffusion that also causes in the metal.The self-diffusion of research iron in having the steel of various lattices.In the steel with body-centered cubic (bcc) and face-centered cubic (fcc) lattice, the ultrasonic iron that accelerated is in the self-diffusion that surpasses under the deformation amplitude of certain threshold value.In addition, regardless of lattice types, effect of ultrasound causes the acceleration self-diffusion of iron.

The most promising technology is to carry out surface treatment with ultrasonic tool, and this shock action by " the deformation effect element " of accepting energy from the sonic oscillation transverter is implemented.This technology provides significant surperficial microhardness, residual compressive stress and slide frictional property.Plastic deformation (occurs under the impact of " deformation effect element " at pressure head in the surface.Deformation character is by rapid ultrasonication and simultaneously introduce (via the plastic deformation zone of saturation) high function sonic oscillation in the material and determine, this vibration causes relaxing of high-strength ultrasonic under the cyclic stress level in strong creep zone and material stress state therein.When this situation occured, also therefore the repeatedly plastic deformation that point of contact (in the regional area of ultrasonic impact effect) generation is accelerated produced strong heating the (being enough to recurring structure changes) and rapid cooling (being enough to make in stable conditionization of transition phase).Therefore, form from the teeth outwards the material with the new property that is caused by structural changes.

In order to ensure the parts of engineering system and the reliability service of structure, monitor their technical qualification and adopt the technical measures that prolong its life-span.When the technical qualification of monitoring complex system and equipment, one of most realistic task is objective and detects in time various defectives and control their development, because parts timeliness in use.It is a kind of mode that prevents the not desirable consequence in the defective parts use that the system of non-destructive method uses.

In order to prolong component life and to recover its performance; use following basic skills according to the types of degradation that they stand: thermal treatment is with the performance of change structure and improvement component materials; heat and vibration treatment are so that residual stress relaxation, removal stress concentration, protective coating, inhibitor and protective material; the surface hardening of being undertaken by the thermo-chemical treatment method, and/and the surface hardening undertaken by surface plasticity deformation (SPD) method.SPD is one of simple effective method that strengthens weld seam and mechanical part.They are because following positive effect and effectively: the raising of dislocation desity and microhardness, therefore the improvement of upper layer wear resistance, the establishment of residual compressive stress in the upper layer of parts, and suppress the effect that the safe range of stress of stress concentration butt welded seam and solder flux parts reduces.

It is one of the most promising SPD method that ultrasonic impact is processed (UIT).In the UIT method, when therein excitation ultrasound vibration, the anti-plastic deformability of material temporarily reduces, and obtains the large enhancement Layer degree of depth.This causes high plastic deformation degree and high residual compressive stress level of being brought out by processing.UIT also is accompanied by surface heat machinery and the inferior surface relaxation effect in the material of processed product.

Be known that equally Degradation, Repair and Rebuilding of Bridges (bridge Deteriorated, repair and rebuild)(Materials Information/Cambridge Scientific Abstracts, 2005, ISBN 0-88387-217-X), it discloses highway and railway bridge and bridge construction material, comprises the deteriorated of structure high strength and the form of ownership of reinforcing steel, Steel Concrete, polymer concrete and reinforced plastics.Also disclose anticipation, ongoing or completed repairing and reconditioning technology/effort, material selection and replacement and corrosion prevention and control.

Be known that equally Preliminary Study Into The Effect Of Exfoliation Corrosion On Aircraft Structural Integrity is (to degrading aircraft structural integrity The preliminary study of impact), N.C.Bellinger, J.P.Komorowski, M.Liao, D.Carmody, T.Foland, D.Peeler work (6 ^ThJoint FAA/DOD/NASA Aging Aircraft Conference, 2002), it has been listed as determining to peel off the result of the research that the impact of the residual life of top wing shell is carried out.Downcut many coupons from the top wing shell of being made by the 7178-T6 alloy that naturally peels off.These coupons (some of them provide the low load transmission through fastening piece) contain various level of exfoliation.Use the compression controlled load of constant amplitude to test each coupon to losing efficacy.Then check that fracture surface is to measure the fracture origin.The sample invalid position is indefinite, and it also is like this that crackle plays the source position.The crackle origin comprises the discontinuity of plane cracking (peeling off), fretting, spot corrosion and manufacturing owing to several reasons.Result so far shows that for tested level of exfoliation, stripping gets blamed and controls the key factor in top wing shell life-span.

Corrosion in the airframe is remarkable economy and the safety problem that affects a military and civilian flyer group of planes.United States Air Force (The United States Air Force) oneself estimates that the directly etching loss surpasses $ 800M/.Corrosion has many forms and affect most structural alloys of nowadays finding in fuselage.One of modal problem is degrading of influence of rolled plate and wrought alloy.Peel off in the top wing shell of being everlasting in the fastener hole found around, wherein it originates from the end grain of the exposure in countersunk and boring surface.

In ASTM G15-97a, degrade or peel off and be defined as from " initial " position along the face parallel with the surface, usually at grain boundaries, the corrosion of lateral extension forms and forces metal to break away from the corrosion products of material bodies, thereby produces the outward appearance of layering.In other words, peeling off is a kind of form of serious intergranular corrosion, and it occurs at the grain boundaries with the rolling direction elongation.The remarkable directional correlation of this Corrosion Types and crystalline-granular texture.In flyer, material denudation is most commonly in heat treatable Al-Mg-Zn (7000 series), Al-Cu-Mg (2000 series) and Al-Mg alloy, but it also can be observed in the Al-Mg-Si alloy.The generation of degrading product forces layer separately and causes the metal parts swelling.Sheet metal may by on push away and even peel off from the surface.

Find to only have 11 to attempt to solve and peel off and fatigue problem to surpassing 80 reviews about the open source literature that degrades.The Main Conclusions of peeling off with tired repercussion study formerly can be summarized as follows:

(1) formerly peel off the crack nucleation that accelerates fatigue;

(2) peeling off and improved fatigue crack growth speed (FCGR) formerly;

(3) peeling off and cause multiple spot to destroy the more early outbreak of (MSD) formerly;

(4) cause some reasons of above-mentioned mechanical phenomenon to be: spillage of material (cross section reduces or thickness reduction); Hydrogen embrittlement (toughness of reduction, intensity and Material ductility); With other chemical effect; With

(5) formerly peel off and tired the interaction is not only economic problems or safety problem.Quantitative relation between pull out type fracture and remaining fatigue lifetime and the residual strength is not yet definite.

Some researchs show, may repair intensity and the fatigue property that reduces structure than grinding when peeling off around being present in fastening piece with lacking.In Australia, applying of anti-corrosion compound (CPC) stoped some pulls out type fracture in the C-130 aircraft, and this aircraft need not to eliminate to peel off and can recover to use.Seek help from the decision of CPC based on the indication from laboratory experiment, namely CPCs stops corrosion and the crack growth in corrosive atmosphere very effectively.

Be known that equally Fatigue Degradation and Failure of Rotating Composite Structures-Materials Characterisation and Underlying Mechanisms (the tired deteriorated and inefficacy-bill of material foundation machine of seeking peace of rotation composite structure System), E.Kristofer Gamstedt, Svend Ib Andersen work (Riso National Laboratory, Roskilde, Denmark, 2001), it discloses the rotation composite structure, wherein tired deteriorated with use in inefficacy important relationship is arranged.This application is, for example, and the rotating vane in the wind turbine, helicopter rotor blade, the wind wheel, navigation and the airscrew that are used for stored energy and the roller of paper machine.Purpose is to find out make urgent effort utilizes matrix material better in these are used field.In order to obtain to obtain the better method of design of more reliable and elongated structure, improved test method must be arranged.In addition, compare with present case, should be better the relation between solution structure, parts and the specimen test result.Improved Forecasting Methodology depends on understands foundation failure mechanism better.In the model based on mechanism, can the optimization component substructure or even material microstructure to obtain possible best fatigue resistance.In this report, solve these problems, emphasize specially test method, and comprise from failure mechanism to associated materials character.

Be known that equally Metal Properties Degradation in Main Pipelines After Prolonged Service (metalline behind life-time service in the main pipe line is deteriorated), G.A.Filippov, O.V.Livanova and V.F.Dmitriyev work (" Steel ", No.2,2003), it discloses the result of operational conditions on the first part of comprehensive research of the impact of pipeline character.In Russia, most main pipe lines used above 20 years.Be subjected to the impact of stress, corrosive environment and hydrogen to reach the time of such length, pipeline is bearing the process of the physicomechanical properties that changes metal.The actual nature that must consider tube metal with analysis condition, assess residual life and arrange the maintenance process of pipeline.The pipeline premature failure mainly be by the stress concentration (cut, otch, textural defect etc.) in machinery source with by causing with the defective that contacting of corrosive atmosphere forms by metal.Life-time service causes tube metal character because metal construction change of state and deteriorated, even and also may lose efficacy under the stress that is lower than the stress upper limit.The resistance to rupture that reduces may be relevant with the accumulation of the raising of ageing of metal process, hydrogen richness and internal stress and defective (such as tiny crack).

The analytical results that carries out in the pipe samples of obtaining from 19 main oil pipes that are arranged in various weathers is disclosed at experimental installation tested steel 20,17MnSi, 17Mn1Se, 19Mn, 14CrMnSi, the 15MnSiTiAl of Central Research Institute of Ferrous Metals, the sample of 10Mn2Si1,14MnNi.In all studied pipelines, the roughly chemical constitution per-cent of steel is as follows: steel 17MnSi, 17Mn1Si and 19Mn-81% (difference 37%, 19% and 25%), steel steels 20 and 14MnNi-each 1%, steel 15MnSiTiAl, 10Mn2Si1 and 14CrMnSi-difference 3%, 5% and 9%.The difference that the grade of steel 17MnSi, 17Mn1Si and 19Mn forms is carbon and manganese content.But the chemical analysis of pipe samples shows that the actual composition of steel usually and industrial certificate is inconsistent and therefore these steel are carried out basic statistical study, further is known as the steel of 17MnSi type.Research 106 samples altogether, 86 from operating pipeline, 9 from emergency stock, 7 from emergent pipeline, 3 from the reinforcement pipeline, sample pipeline when dispatching from the factory.In addition, study the Piping specimen of many welding, majority is that factory vertically welds.All site welding and 8 vertical welding of factory all have defective.

The stretch characteristic of standard is not enough to assess the situation of main pipe line.The reliability assessment standard should comprise the character to the local structure sensitive, the character that for example obtains from low-temperature test, delayed fracture test and the test to cracking and sharp notched specimen.In the sharp notch bending test of the sample after using 25 years, find that all failure resistances of metal all reduce.Energy-to-break reduces half mainly due to the reduction of cracking patten nucleus power.The cold shortness threshold value is shifted to positive temperature province.The crackle critical opening reduces by 1.5 times.Delayed fracture trend under steel acts in stress, corrosive environment and hydrogen it is found that structure deteriorate the most responsive.The reduction of the resistance to fracture of tube metal in the life-time service process is relevant with the accumulation of strain ageing process and defective and inner microstress.

Be known that equally Assessment of Age-Related Degradation of Structures The and Passive Components for U.S.Nuclear Power Plants (knot of USA Nuclear Power Plants The deteriorated assessment of timeliness dependency of structure and passive element)J.I.Braverman, CH.Hofmayer, R.J.Morante, S.Shteyngart and P.Bezler work (NUREG/CR-6679, BNL-NUREG-52587,2000), it has described the achievement of the fs of the deteriorated for many years research project of the timeliness dependency of the structure of assessment USA Nuclear Power Plants and passive element.The purpose of this research project is to develop to can be used for making risk announcement decision and solution and the analytical procedure of the deteriorated relevant technical problem of structure and passive element and checking and the improved technical foundation of standard for acceptance.The method that is used for this research project comprises three phases.The I stage comprises collection and the assessment of device deterioration event, to the assessment of the deteriorated available techniques information of timeliness dependency, and determines that the scoping that should study which structure and parts in the subsequent stage of this research project studies.Based on the achievement in I stage, use existing and improved analytical procedure to evaluate and test selected structure and passive element with the deteriorated impact of assessment timeliness dependency in the stage at II.The III stage utilizes the achievement of this analysis in order to propose to announce the suggestion that determines about making with the deteriorated relevant risk of structure and passive element to NRC employee.

Be known that equally The History of Cracking the RCPB of Swedish BWR PlantsKaren Gott work (9th International Conference on Environmental Degradation of Materials in Nuclear Power Systems-Water Reactors, 1999), it proposes the result of the technical qualification of the used equipment of monitoring Sweden Nuclear power plants.The Nuclear power plants of Sweden is required to report all crackles to Swedish Nuclear Power Inspectorate (SKI).This regulations are applicable to relate to all systems that the SKIs regulations of the structural integrity of mechanical part cover.Therefore, SKI has collected the bulk information relevant with the history of the various degradation mechanisms of observing in Sweden's Nuclear power plants over many years.In nearest 2 years, the database that this input information is set up for this purpose specially.Information in the database comprises details and system and the parts details that when and how to detect crackle, its size and the origin cause of formation.This database also has the comprehensive with reference to list of all associated documents relevant with crackle or crackle group.With the trend of in the reactor coolant pressure boundary limit (reactor coolant pressure boundary (RCPB)) of Sweden's boiling water reactor (Swedish boiling water reactors (BWR)), finding this database and its application of illustration are described.

Be known that equally Degradation of Spacecraft Materials be (the flyer material Deteriorated)J.Dever, B.Banks, K.deGroh and S.Miller (NASA Glenn Research Center, 2004), it discloses the particular space environment to the description of the threat of outside air material material but has not solved environment to the impact of outside aircraft system and electron device.Summarized the laboratory simulation that aviation exposes research and independently threatens with comprehensive aeronautical environment.Emphasized the impact of earth orbital environment, because most of aviation mission is to fly, provide quite a large amount of data about material effect in Earth's orbit.Also disclose and the problem of explaining that the material degradation result is relevant, and will identify the deficiency of ground test.Recommendation is selected to reduce by suitable material or is prevented that aeronautical environment is deteriorated.

Therefore, used parts and structure is all deteriorated easily in nearly all engineering field.Deteriorated problem is the most serious for engineering system, and its inefficacy may cause catastrophic consequence, for example personnel death, ecological damage and serious spillage of material.These comprise: transportation (bridge, tunnel, railway, load transportation structure and lift installation); Oil ﹠amp; Gas and chemical plant (main pipe system, bunkie station, distillation and other chemical facility); Aircraft (aircraft of all kinds and purposes); Power system (nuclear power apparatus of Nuclear power plants and electric power supply system thereof, thermoelectric power station); Airline (outer space vehicle, emission and rocket system); With large military installations.

Correspondingly, metal is deteriorated to be metallic substance owing to the process that microdefect and formation and extension of cracks damage, and this causes the loss of large crackle and parts weight bearing power.Therefore, the total that comprises these parts may lose efficacy.

It is one of most realistic problem of facing of whole world scientist and engineering scientist that the work-ing life of maximum possible, the problem that hinders the timeliness of this base part and structure and prolong its useful life are provided.The appearance of failure or defective may cause catastrophic effect in engineering system, for example global disaster, environmental degradation, loss of life and personal injury and serious finance and material unaccounted-for (MUF).

Do not have systems approach, the research in this field is impossible.Various measures and task solution that can the improved system condition be guaranteed suitable reliability and the prolongation in work-ing life in the situation that takes into account economic yardstick and restriction.

Before, inefficacy is regarded as inevitable event.Each material is considered to have certain structural strength.But, at present, exist and not only assess degradation and provide prediction also to block deterioration process and even repair method and the mechanism that product or parts prolong its work-ing life thus.That is to say that material degradation is the process that can control.

One of promising direction of deteriorated and its performance of recovery of retarding construction material is to apply UIT.Except the traditional effect that obtains by the SPD method, for example outside the microhardness of high pressure stress level, raising and the inhibition stress concentration effect, UIT also is accompanied by the lax of unrelieved stress; Ultrasonic diffusion in the material; The recovery of deteriorated material character; Decrystallized with material structure under the ultrasonic impact effect.

Purpose of the invention and overview

The present invention relates to improve metallicity and prevent method and the algorithm (algorithm) that metal is deteriorated and inhibition is deteriorated by ultrasonic impact.The method and algorithm put forth effort to solve the deteriorated problem of the metallicity in the life-time service process under external force, thermodynamic fluctuations and Negative Environment's.The invention still further relates to the technology of the danger of the material failure that causes for opposing (preventing) and the unfavorable variation that can occur in time of inhibition do as one likes.These problems are usually destroyed by the primary formation of material under the known conditions of the environment deterioration process that is accompanied by metal and are caused.Under each particular case, the deteriorated method of known " antagonism " metal comprises multiple technologies, applies metallurgical alloy the process to lip-deep various thermal treatments and effect from melting, casting, welding and coating.

The invention provides the new universal method and the algorithm that in all above-mentioned situations, solve deteriorated problem.The below describes method and the algorithm of the affected object of this processing in detail.

The metal edges interlayer is on the response of this effect and before this technical effect and the characteristic of character afterwards and situation remarkably influenced sub-surface layer, and it determines that in combination the technology of the method renders a service separately or with surface property.The effect degree of the ability of the material property that the effectiveness of the method and/or algorithm refers to the change in orientation by material character and structure is caused, the stress-deformation state of structure and the opposing of this material external force, temperature variation and environmental influence.Therefore, method of the present invention and/or algorithm are considered as two independences with the material of surface and below thereof but the entity and under this background of being mutually related, and the method for the ability that improves the unfavorable factor that the object opposing causes its performance degradation is provided.Therefore, to the requirement of the situation of processed surface and subsurface material, as the relevant but technology effect standard independently of two of the method, determined to affect the technical characterictic of the surface of affected object and material wherein.Correspondingly, the below describes ultrasonic impact method and/or algorithm in detail and has general-use in the engineering field of different origins and the variant of concrete purposes at the performance degradation of object materials.

Method of the present invention and/or algorithm also relate to the task of improving the anti-deterioration of metal.The method and/or algorithm cause the tissue that is determined by task of " soft " of ultrasonic impact and power stdn phase place and control and realization (by its generation) and are actually used in the technology that suppresses deteriorated and render a service (according to the method for the present invention of using ultrasonic impact to control)." soft " refers to phase place and the parameter of ultrasonic impact---its meet task and in the time might determining the shock resistance of material and in the processed zone of material according to impact phase place when certain minimum shock resistance occurring directly the predetermined or experiment of control material determine state, strengthen (plastic deformation) thereby when keeping the middle structural integrity of processed material, produce possible maximum.

The tissue of " soft " of ultrasonic impact and power stdn phase place and the main phase of control preferentially comprise following:

-forming subsequently the dynamic strength of assessment material under the background of structure in the best at body surface;

-select parameter and the degree of depth of the soft or power phase place of control ultrasonic impact according to the method and/or algorithm;

-suppress the deterioration process that has started and preventing under the background of its possibility the definition of the experiment of material surface constructional aspect or analysis expert and modification task thereof;

-determine that by task the intensity of the impact of stdn (according to control method and algorithm) ultrasonic impact effects on surface material structure up and down and the experiment of order or expert select;

-determine at it " soft " after the phase place in the ultrasonic impact process parameter of the impact of the material structure under the power effects on surface and order to keep integrity and to provide the appointment of structure in the lip-deep material to strengthen;

The preparation of-method of the present invention and/or algorithm and the enforcement that links up;

-the match condition of experiment results and technical assignment on the first experimentalists and technicians of sample or simulator;

-with input database as a result; And/or

-in the formation stages of the surface of material and subsurface character, implement take ultrasonic impact control level (selecting by aforesaid method) as basic degradation inhibiting method and/or algorithm.

The accompanying drawing summary

With reference to accompanying drawing:

Fig. 1 (prior art) has shown the brittle state (T of life-span to the tube metal of steel MnSi ₅₀) impact of invert point.

Fig. 2 (prior art) has shown for steel 17MnSi, causes break time t _fWith initial stress specific strength K _iBetween relation, (1) when dispatching from the factory, (2) service pipe, and (3) emergent pipeline.

Fig. 3 (prior art) has shown the impact of using strain ageing trend.

Fig. 4 (prior art) has shown that the area of timeliness pipeline reduces.

Fig. 5 (prior art) has shown the internal friction Q of tube metal after long-term use in 30 years of 17MnSi steel ^-1Temperature dependency.

Fig. 6 (prior art) has shown the internal friction Q of tube metal after long-term use in 30 years of the 17MnSi steel in the emergency stock ^-1Temperature dependency.

Fig. 7 (prior art) has shown the Latent destruction mechanism relevant with the high temperature application of aluminium alloy.

Fig. 8 (prior art) has shown the various classification of hydrogen loss.

Fig. 9 (prior art) has shown the synoptic diagram of electrochemical corrosion course.

Figure 10 (prior art) has shown the synoptic diagram of two electrochemistry stratification of the atoms metal ion that changes into solution.

Figure 11 (prior art) has shown the synoptic diagram of transferring to cationic pair of electrochemical layer stratification on the metallic surface from solution.

Figure 12 (prior art) has shown at the emergency stock pipeline and the integrity of the surperficial microhardness data that the surface of the pipe section (steel X65) of the pipeline after using 20 years obtains.

Figure 13 (prior art) shows that with the clear fractograph Photomicrograph that demonstrates multiaspect (faceted) growth (shear mode growth) surface crack of the starting materials with minute surface facing begins and crack growth.

Figure 14 (prior art) shows that the surface crack through the starting materials of EDM ornamenting begins and crack growth, and it has the nearly surf zone that demonstrates multiple cracks nuclear sign.

Figure 15 (prior art) has shown chink starting position and the crack growth form of S110-200%-45 ° of sample, and it has the multiaspect zone that extends to about 150 micrometer depth and the multiaspect zone that is centered on by the slit-like repeated stress failure.

Figure 16 (prior art) with demonstrate that surface crack begins, the fractograph Photomicrograph of crack branching and extensions path shows LSP 10GW/cm ²The crackle in (2 road) begins to grow with infant cracking.

Figure 17 (prior art) with demonstrate that surface crack begins, the fractograph Photomicrograph of crack branching and extensions path shows LSP 10GW/cm ²The crackle in (3 road) begins to grow with infant cracking.

Figure 18 (prior art) shows that with demonstrating the surface crack that begins from typical shot peening pit and the fractograph Photomicrograph of crack branching the crackle of Duplex treatment begins to grow with infant cracking.

Figure 19 and 20 (prior art) display space center or body centered structure.

Figure 21 and 22 (prior art) display surface centered cubic lattice.

Figure 23-25 (prior art) has shown the main slip cleavage face in simple cubic(al)grating.

Figure 26 (prior art) has shown the microstructure of cast iron.

Figure 27 (prior art) has shown the microstructure of annealing iron.

Figure 28-30 (prior art) has shown that the tension force of the monocrystalline circular specimen of zinc slides.

Figure 31 (prior art) has shown the microstructure of the iron of deformation.

Figure 32 (prior art) has shown the microstructure of unstrained iron.

Figure 33 (prior art) has shown the slip line on the not etching metallographic section of iron.

Figure 34 and 35 has shown oscillatory system, and wherein ultrasonic impact is accompanied by the oscillatory system motion under the elastic restoring force that oscillatory system resilience from the processed surface causes, and is connected to the sonic oscillation of the oscillatory system end on the pressure head.

Figure 36 has shown that the plastic deformation in ultrasonic impact process of the present invention distributes.

Figure 37 has shown the frequency plot of ultrasonic impact.

Figure 38 has shown the at random ultrasonic impact of arbitrary arrangement.

Figure 39 has shown that oscillatory system moves the fragment of (in time) figure.

Figure 40 a-40c has shown in the oscillatory system that is being decreased to the pressure head end face terminal, the velocity vector of oscillatory system in advance, soft contact and hysteresis/soft impact.

Figure 41 has shown the vector diagram of speed of the oscillatory system of Figure 40 a-40c.

Figure 42 has shown the oscilloscope photo of the ultrasonic impact of arbitrary arrangement.

Figure 43 has shown the traditional area of the UIT of weld before forming groove by UIT.

Figure 44 has shown the middle defective in recess edge that is caused by the enhancing of the local excessive under random impact condition in the UIT process.

Figure 45 has shown the middle defective at the groove center that is caused by the enhancing of the local excessive under random impact condition in the UIT process.

Figure 46 has shown the middle textural defect after tradition strengthens sclerosis.

Figure 47 has shown the middle structural state of the method according to this invention at the UIT rearward recess.

Figure 48 has shown that the independence of 30 microns amplitudes and even (in time) of appointment distribute.

Figure 49 has shown that the appointment of ultrasonic amplitude on convex surface para-curve distributes.

Figure 50 has shown that the appointment of ultrasonic amplitude on concave surface para-curve distributes.

Figure 51 has shown according to the appointment amplitude raising of linear law from 0 micron.

Figure 52 has shown the microhardness figure of cast iron.

Figure 53 has shown the residual stress distribution figure of cast iron.

Figure 54 has shown the corrosion strength of the cast-iron structure of untreated sample under 100 micrometer depth.

Figure 55 has shown the improved corrosion strength of the cast-iron structure of sample under 100 micrometer depth that UIT processes.

Figure 56 shown by with not by UIT sample that process and that in tap water, test in the contrast aspect the corrosion.

Figure 57 shown be welded into, use after behind 5 millimeters pinsUIT, after the hardening by hammer, the shot peening, after the TIG finishing, TIG to repair behind the UIT subsequently and the figure improved fatigue resistance of using 3 millimeters steel welded samples behind the nail UIT.

Figure 58 has shown the figure of the improved fatigue resistance of steel welded sample.

Figure 59 has shown the figure of the improved corrosion fatigue strength of steel.

Figure 60 has shown the figure of the test-results of improved steel drift hit intensity.

Figure 61 has shown the sub-structure of high-strength steel, and it has shown that crystal grain reduces scope.

Figure 62 and 63 has shown the white layer in the 10Mn2Vb steel weld of main pipe line and in the high-strength steel SUJ2 sample.

Figure 64 and 65 has shown the impact of UIT on the welding metal crystallization in the welding carbon ship steel.

Figure 66 and 67 has shown the improved mechanical properties of steel sample.

Figure 68 has shown the S-N graphic representation of 8 millimeters butt welds, and it has shown the safe range of stress of the sample of being made by aluminium alloy.

Figure 69 has shown the S-N graphic representation of 8 millimeters samples with vertical tie point, and it shows the improvement of the high-cycle fatigue strength of weld seam in the aluminium alloy.

Figure 70 has shown the S-N curve of 8 millimeters samples of overlap joint, and it has shown the improvement that shows the high-cycle fatigue strength of weld seam in the aluminium alloy.

Figure 71 and 72 has shown the life of the casting tire of making to the inhibition of the maximum 2.5 millimeters hole of the degree of depth with by aluminium alloy.

Figure 73 and 74 has shown the shock strength that keeps in the processing of the casting tire of being made by aluminium alloy.

Figure 75 and 76 has shown the precipitation of silicon in the aluminium alloy.

Figure 77 has shown the microhardness distribution plan of the precipitation of silicon in the aluminium alloy.

Figure 78 and 79 has shown the improvement of the intensive property of aluminium alloy behind the corrosion spalling.

Figure 80 has shown that UIT according to the present invention is on the impact of the fatigue resistance of sample with different extent of corrosions.

Figure 81 and 82 has shown the refining structure of aluminium alloy.

Figure 83 has shown that the microhardness distribution plan in the process appears in throw out migration in aluminium alloy and little band.

Figure 84 and 85 has shown that throw out migration and the little band in aluminium alloy occurs.

Figure 86 and 87 has shown the raising of corrosion fatigue strength in the bronze.

Figure 88 has shown the deteriorated figure of the environment of metal.

The detailed description of preferred embodiment

The present invention relates to improve metallicity and prevent the method that metal is deteriorated and inhibition is deteriorated by ultrasonic impact.The method puts forth effort to solve the deteriorated problem of the metallicity in the life-time service process under external force, thermodynamic fluctuations and Negative Environment's.The invention still further relates to the technology of the danger of the material failure that causes for opposing (preventing) and the unfavorable variation that can occur in time of inhibition do as one likes.These problems are usually destroyed by the primary formation of material under the known conditions of the environment deterioration process that is accompanied by metal and are caused.

The various environment types of degradation of metal are presented among Figure 88.Deteriorated burn into hydrogen loss, liquid-metal corrosion and the radiation destruction of comprising of the environment of metal.Corrosion comprises aqueous corrosion and high temperature corrosion.Aqueous corrosion can be general corrosion or local corrosion.The local corrosion of aqueous corrosion can comprise galvanic corrosion, crevice corrosion, spot corrosion, intergranular corrosion, selectivity leaching, erosion-corrosion or corrosion cracking.High temperature corrosion comprises burning and thermal etching.Burning can comprise hydrogen embrittlement, hydrogen foaming, platelet exfoliation, white point and broken crackle, or hydrogen attack.Hydrogen embrittlement can comprise stretching ductility loss, hydrogen stress cracking, hydrogen environmental embrittlement or be formed the embrittlement that causes by hydride.Liquid-metal corrosion can comprise Liquid Metal Embrittlement, crystal boundary infiltration and/or liquid metal corrosion.Radiation destruction comprises creep and/or radiation intensification and the embrittlement of radiation growth, space swelling, radiation intensification.

Under each particular case, the deteriorated method of known " antagonism " metal comprises multiple technologies, applies metallurgical alloy the process to lip-deep various thermal treatments and effect from melting, casting, welding and coating.The invention provides the novel method that in all above-mentioned situations, solves deteriorated problem.The below describes the method for the affected object of this processing in detail.

The metal edges interlayer is on the response of this effect and before this technical effect and the characteristic of character afterwards and situation remarkably influenced sub-surface layer, and it determines that in combination the technology of the method renders a service separately or with surface property.The effect degree of the ability of the material property that the effectiveness of this treatment process refers to the change in orientation by material character and structure is caused, the stress-deformation state of structure and the opposing of this material external force, temperature variation and environmental influence.Therefore, method of the present invention is considered as two independences with the material of surface and below thereof but the entity and under this background of being mutually related, and the method for the ability that improves the unfavorable factor that the object opposing causes its performance degradation is provided.To the requirement of the situation of processed surface and subsurface material, as the relevant but technology effect standard independently of two of the method, determined to affect the technical characterictic of the surface of affected object and material wherein.Correspondingly, the below describes the ultrasonic impact method in detail and has general-use in the engineering field of different origins and the variant of concrete purposes at the performance degradation of object materials.

Method of the present invention relates to the task of improving the anti-deterioration of metal.The method causes the tissue that is determined by task of " soft " of ultrasonic impact and power stdn phase place and control and realization (by its generation) and is actually used in the technology that suppresses deteriorated and renders a service (according to the method for the present invention of using ultrasonic impact to control)." soft " refers to phase place and the parameter of ultrasonic impact---its meet task and in the time might determining the shock resistance of material and in the processed zone of material according to impact phase place when certain minimum shock resistance occurring directly the predetermined or experiment of control material determine state, strengthen (plastic deformation) thereby when keeping the middle structural integrity of processed material, produce possible maximum.

The tissue of " soft " of ultrasonic impact and power stdn phase place and the main phase of control preferably include following:

-forming subsequently the dynamic strength of assessment material under the background of structure in the best at body surface;

-parameter and the degree of depth of the soft or power phase place of ultrasonic impact controlled in selection according to the method;

-suppress the deterioration process that has started and preventing under the background of its possibility the definition of the experiment of material surface constructional aspect or analysis expert and modification task thereof;

-determine that by task the intensity of the impact of stdn (according to control method) ultrasonic impact effects on surface material structure up and down and the experiment of order or expert select;

-determine at it " soft " after the phase place in the ultrasonic impact process parameter of the impact of the material structure under the power effects on surface and order to keep integrity and to provide the appointment of structure in the lip-deep material to strengthen;

The preparation of-method of the present invention and the enforcement that links up;

-the match condition of experiment results and technical assignment on the first experimentalists and technicians of sample or simulator;

-with input database as a result; And/or

-in the formation stages of the surface of material and subsurface character, implement take ultrasonic impact control level (selecting by aforesaid method) as basic degradation inhibiting method.

Ultrasonic impact is accompanied by two kinds of type of sports: as shown in Figure 34 and 35, (1) the oscillatory system motion under the elastic restoring force that oscillatory system resilience from the processed surface causes, and (2) are connected to the sonic oscillation of the oscillatory system end on the pressure head.As shown therein, basic tool comprises at least one pressure head 103, waveguide 102, the magnetostrictive transducer 101 with shell 107 (it is water cooled housing), spring 106 and is with handled tool outer casing 105.The shell 107 of magnetostrictive transducer 101, waveguide 102, pressure head 103, tool outer casing 105, spring 106 and transverter consists of oscillatory system (OS), and it has the process unit that structurally is fixed to the upper.

The below be in the whole specification sheets of the present invention and accompanying drawing in used abbreviation index:

The OS-oscillatory system;

The oscillatory system that OSE-is connected on the pressure head end face is terminal;

The surface that TS-is processed;

The UI-ultrasonic impact;

V _OsThe hunting speed of-oscillatory system;

V _OseThe hunting speed of-OSE under ultrasonic frequency;

V _r-during certain at V _OsAnd V _OseSummation in the co oscillation speed of OSE;

M _Os-oscillatory system quality;

P _Tmp-ultrasonic impact linear impulse;

f _OsThe frequency of the vibratory movement of-OS (200Hz);

f _OseThe frequency of the vibratory movement of-OSE (27000Hz);

A _OsThe displacement amplitude of the vibratory movement of-OS (0.3 millimeter);

A _OseThe displacement amplitude of the vibratory movement of-OSE (0.03 millimeter);

The phase place of Ψ-sonic oscillation;

F=OS is to the plus-pressure of TS.

Figure 36 has shown that the plastic deformation in ultrasonic impact process of the present invention distributes.The average statistics ultrasonic impact is included in three timed intervals (being designated as a, b and c in Figure 36) that act on the object, and it has stipulated the plastic deformation distribution intensity in the material processed in each impact event process.These intervals comprise: (a) is in the narrow gap of processed surface and oscillatory system end, in the pressure head vibration under the frequency of increasing progressively of the carrier frequency that is higher than ultrasonic transducer as shown in Figure 37; (b) the uninterrupted vibration of the synchronous and homophase in system's " oscillatory system-pressure head-processed surface "; (c) because oscillatory system resilience from the processed material, the dying oscillation that increases progressively pressure head in the gap between processed surface and oscillatory system end.

When this situation occurs, the resilience of oscillatory system and impact event are compared with the sonic oscillation (carrier frequency oscillation of ultrasonic transducer) of the output end of oscillatory system and are occured at random and form as shown in Figure 38 random phase figure, it shows beginning and end and three timed intervals thereof of each ultrasonic impact event, i.e. (a), (b) and (c).

Oscillatory system movement velocity and with the at random addition of sonic oscillation speed of the oscillatory system end of pressure head causes the dynamic overload problem of the dynamic strength limit that exceeds structure in the processed surfacing on the surface that affected by ultrasonic impact.This causes again following point: (a) on the surface distress that middle structure deteriorate causes, and the dissipation of striking energy, and these damage the unfavorable expansion in impacting subsequently; The intensity of the plastic deformation of (b) in surfacing, bringing out and the degree of depth and by the reduction of its favourable stress that causes; (c) in the material of affected object, sonic oscillation energy and the therefore reduction of ultrasonic stress waves in soils.These factors are so that ultrasonic impact Disposal quality control difficulty and reduced its technology and renderd a service, and namely as one man are reproduced in the surface and the ability of predetermined structure, situation and the character of the processed material at designated depth place under the surface.

Metal deteriorated is accompanied by wherein structural damage, mainly is in upper layer.The dynamic strength of surfacing is determined according to relational expression V=2 σ/ρ C by surface deformation speed, wherein σ is the dynamic tensile strength under given load speed, ρ is density of material, C is at sound or is out of shape the speed of propagating in material, V is the speed of action before or after the surface distress, and ρ C is the resistivity to effect (dynamically, sound, quasistatic).

Calculating shows in ultrasonic frequency range, to have for the sizable deposit that improves ultrasonic impact intensity.Therefore, under the frequency of 30 microns ultrasonic amplitudes and 27kHz, hunting speed is 5.5 meter per seconds and is that critical velocity under the dynamic action on the steel of 700MPa is 34 meter per seconds in yield strength.This can become higher ultrasonic impact carrier frequency more feasible in the practice of maximum 80kHz.This deposit is very responsive to atarting material character deteriorated external factor and environment in long-term time course.The use of the control method of therefore, developing is real at the structure of the high loading metal construction of key with in safeguarding.

Therefore, we must solve triple technical assignments, comprising: (a) in the ultrasonic impact process control material in structure to keep it in processed lip-deep integrity; (b) recover structure in the deteriorated material; (c) directly structural state and the character of the processed surface of impact material up and down in the ultrasonic impact process.

This technical assignment requires again in (a) oscillatory system near processed when surperficial, (b) directly in the ultrasonic impact process, if proofread and correct in addition with needing, (c) when testing definite ultrasonic impact at (a) and finish between the action period to processed surface (b), form independently the sonic oscillation condition.

As implied above, the ultrasonic impact facture is accompanied by two kinds of mode of oscillation: (a) low-frequency oscillation of oscillatory system lumped mass, and (b) coupling resonance element, the i.e. ultrasonic frequency of the transverter-waveguide of oscillatory system-pressure head vibration.The concrete calculated example of the part of the figure of these motions and amplitude velocity relation thereof is as being presented among Figure 39.

Positive amplitude is equivalent to OS near TS.Calculating in displacement, speed and the acceleration of any given time t is: x (t)=Acos ω t; V (t)=-A ω sin ω t; A (t)=-A ω ²Cos ω t.Top speed is A ω.Therefore, the top speed of OS and OSE is as follows:

V _Os=2A _Osπ f _Os=0.38m/sec (maximum value); And

V _Ose=2A _Oseπ f _Ose=5.09m/sec (maximum value).

Can find out that oscillatory system motion is accompanied by two kinds of frequency type of hunting speed, wherein at least 1 magnitude of the leading active hunting speed of carrier frequency sonic oscillation speed (oscillatory system with this speed near processed surface).

Therefore, method of the present invention comprises following two kinds of main situations:

(a) before sonic oscillation speed obviously surpass to be impacted near the speed of the oscillatory system on processed surface (especially, as implied above, in the 27kHz frequency with 30 microns ultrasonic amplitudes with under the 200Hz resilience frequency under the 0.3mm amplitude); With

(b) in the moment corresponding with the timed interval; the rapid variation of oscillatory system mode of oscillation (more properly; at number period of oscillation of specifying under the driving pulse energy; comprise the compensation transient process); between sonic oscillation speed when it is enough to obtain velocity of approach and impacts beginning the appointment of summation reduce, compensation or raise with structure in the protection preventing disadvantageous destruction, and in impact process, directly affect the structure and characteristics of processed material by processed surface.

The effect phase place of structure in to material of condition-with this understanding namely impacts forming method for controlling impact-be presented among Figure 40 a-40c in the phase place.More particularly, Figure 40 a has shown " shifting to an earlier date ", and wherein the vector of the hunting speed of OS and OSE has a direction, the sum velocity of OSE, V _rBe maximum value.When OSE contact TS, maximum impact pulse P _ImpTransfer to wherein.Figure 40 b has shown " soft contact ", and wherein OS closes the opposite and sum velocity V of vector of the hunting speed of OSE _rWhen contact TS, be " 0 ".More particularly, when the contact beginning, the ultrasonic component of shock pulse is " 0 ".Figure 40 c has shown " hysteresis/soft contact ", and wherein to close the vector of hunting speed of OSE opposite for OS.The sum velocity of OSE (in contact area) is minimum value.Shock pulse is minimum value.

Therefore, when oscillatory system finishes the variation of sonic oscillation speed with the phase place of OSE coupling in produce the initial prerequisite of the power pulse that is used for control shock point place: " rigidity " from the hunting speed addition time, to respectively when hunting speed equates or " soft " contact when sonic oscillation speed surpasses oscillatory system velocity of approach under ultrasonic frequency or impact.The vector diagram of this class state of this class oscillatory system of the present invention for example is presented among Figure 41.

The figure of Figure 41 is clear to be presented between oscillatory system and the processed surface " soft " of the position of first contact and to impact and form mechanism.The stack of this mechanism on the actual oscilloscope image of real impact for example is presented among Figure 42.When soft contact, the resultant of the sonic oscillation speed of OS and tool is 0 (0) when impacting beginning.When soft impact, the sonic oscillation sum velocity of OS and tool is negative when impacting beginning.When rigid shock, the sonic oscillation sum velocity of OS and tool is maximum value when impacting beginning.

Figure 43 has shown the traditional area (* 10) by the UIT of Han Jiedian before the UIT formation groove.Figure 44 and 45 has shown the middle textural defect type behind UIT under the random impact condition, wherein Figure 44 has shown the middle defective in recess edge that is caused by the enhancing of the local excessive under random impact condition in UIT (* 40) process, and Figure 45 has shown the middle defective at the groove center that is caused by the enhancing of the local excessive under random impact condition in the UIT process.

Figure 46 has shown the middle textural defect after tradition strengthens sclerosis, i.e. defective in the surface after knocking sclerosis (* 160).Figure 47 has shown structure, the i.e. state of the middle structure of groove during the method according to this invention is behind UIT.

Following from Figure 47, by according to aforesaid method control ultrasonic impact parameter, form surface and the middle structure on processed surface, it does not have to cause the destruction of the expansion of deteriorating effect in given weld use procedure.In addition, under at least 1.5 millimeters the degree of depth, strong plastic deformation is regional as seen, and generation prevents from the reliable physical barrier layer that this class is destroyed occurring in the concentrated point of geometrical stress zone under working load in long process again.These effects of following more detailed description.After " soft contact " or " soft ultrasonic impact ", form the task of enhancement layer by the method solution of the part of formation method of the present invention, the method comprises the zone of saturation (having structure in the best) of the plastic deformation that causes by the soft ultrasonic impact by maximum (aspect processed surface strength) power, by the inverse task that excite of ultrasonic stress waves in soils (maximum value for given material) in upper layer and material of ultrasonic impact initiation.

This task has determined the control parameter of the ultrasonic impact of superpower control in the treating processes of sub-surface layer.As mentioned above and shown in, in order to protect processed surface to prevent middle structure deteriorate and in the zone of saturation, to produce plastic deformation in order to make the best continuity under the minimum dispersion loss of surface of UIT method, therefore " soft " phase place of ultrasonic impact is necessary, and makes: (a) separate with the surface and effective sonic oscillation of the pressure head of the oscillatory system synchronous with it; (b) be combined with the protective nature on modification surface, exciting under enough high-power ultrasonic stress waves in soilss is to suppress appearance or the expansion of the deteriorated start-up course of material character.

Figure 48-51 has shown the result of the plastic deformation that changes subsurface processed material after ultrasonic impact " soft " starts under various ultrasonic impact amplitude variations.Especially, integrated oscilloscope photo has shown at it relation between amplitude variations situation of residual surface plastic deformation and the long ultrasonic impact of 1ms after " soft " phase place.The actual free-falling of all results and amplitude in the practical range of values shown in Figure 48 distributes and provides contrastively, and Figure 48 has also shown the identical dependency with 30 microns amplitudes of the actual use of in time equally distributed appointment.Particularly, Figure 48 has shown independently distributing with even (in time) of appointment of 30 microns amplitudes.Figure 49 has shown that Figure 49 has shown that the appointment of ultrasonic amplitude on convex surface para-curve distributes.Figure 50 has shown that the appointment of ultrasonic amplitude on concave surface para-curve distributes.Figure 51 has shown according to the appointment amplitude raising of linear law from 0 micron.

The analysis of the above-mentioned integrated oscilloscope photo of ultrasonic impact (after its " soft " phase place), relevant with consequent plastic deformation, showing can be as affecting material to suppress controlling plastic deformation in wide scope deteriorated or its task of situation occurring of metal determines in each impact event process.Ultrasonic impact is at first determined by specific tasks the physical order of the impact of metal construction.Some general step of this order (comprise from the initial conditions of material and change into the situation that method of the present invention causes) are:

(1) surfacing keeps integrity and the middle structure of surfacing to be enough to fill up the speed deformation of intergranular defective voids in the plastic deformation process of being impacted the phase place initiation by " soft ";

(2) in " soft " and power phase place process of ultrasonic impact, sealing textural defect border under the power that in the plastic deformation process of surfacing, produces;

(3) under the elastic residual stress that the plastic deformation by processed surfacing causes,, comprise the cycle of " soft " and power phase place by standardized ultrasonic impact, activate defective closing of the frontier surface;

(4) by impacting under the pulse of the power that produces under its repetition rate, activate defective closing of the frontier surface;

(5) under the ultrasonic impact effect, activate defective closing of the frontier surface, the vector of hunting speed and determined by the relation between the movement velocity of oscillatory system lumped mass and distributed mass wherein, therefore the sonic oscillation process neutralization of oscillatory system end in the power pulse process that ultrasonic impact causes, is decreased to oscillatory system end (having pressure head) in the phase place of being stipulated by the control method of vibration sum velocity;

(6) in shock pulse and ultrasonication process, under the frictional force that the displacement by the defective border causes, activate defective closing of the frontier surface;

(7) in the power pulse process that is caused by ultrasonic impact, under through the sonic oscillation of closed boundary and ultrasonic stress waves in soils, activate defective closing of the frontier surface;

In the pulse action process of (8) in by the phase place of control method regulation, reappearing with the ultrasonic impact repetition rate that is determined by material character and effect task, in the rising temperature province that plastic deformation and friction by textural defect border and fragment place cause, activate defective closing of the frontier surface;

(9) under static pressure, power pulse, friction, heating and sonic oscillation, ultrasonic self-diffusion and the annihilation of closed boundary;

(10) activate the precipitation of alloy phase, the silicon throw out in the Al alloy for example, this causes the improvement of the strength of materials when the method according to this invention control ultrasonic impact;

(11) with the Al alloy in the similar unstable phase of copper be fixed on that " soft " is ultrasonic to be contacted and subsidiary assault phase, thereby prevent in sosoloid precipitation and prevent deteriorated expansion;

(12) with the Al alloy in copper similar, activate sedimentary " oppositely " self-diffusion in the sosoloid, this throw out causes the weakening structure key and produce the subsequently deteriorated nuclear of metal of the structural stress centrostigma conduct of hiding under external force; Reverse self-diffusion in this case is the means of recovering among its " soft " phase place and afterwards the strength and ductility of the forfeiture of alloy under standardized ultrasonic impact;

(13) reduction of potential stress concentration point distribution density improves in the process of fatigue resistance under for example owing to the nanostructure level, according to control method of the present invention, owing to its " soft " is activated mutually migration with afterwards stdn ultrasonic impact among starting;

(14) active material Structural Self-Control system under ultrasonic impact, wherein on nanometer, microcosmic and the macrostructure fragment aspect of processed material, be fit to the rotation of its task, bending, twinnig, recrystallize, flow, in slip, surrender and the timeliness, " soft " phase place of ultrasonic impact and the stdn of ultrasonic impact parameter meet the favourable variation of appointment of the structure of processed surface and processed material;

(15) as the means that improve anti-deterioration, under the stdn ultrasonic impact, activate segmentation, homogenizing and the arrangement of microscopic level metal construction, wherein as being determined by task, control " soft " phase place, and after this with the ultrasonic impact standard parameter;

(16) by tissue " soft " phase place and as the impact of the process that the ultrasonic impact standard parameter caused determining of task under activation decrystallized-as the nano level final optimization pass mode of surface metal structure;

(17) method of using " soft " of control ultrasonic impact and power phase place with prevent metal at the deteriorated forming core under the initial conditions, prevent and suppress object materials among its life-time service or afterwards deteriorated;

(18) based on the experiment and the expert data that obtain by above-mentioned any method; use " soft " of ultrasonic impact at random and power phase place with protecting materials to prevent the deteriorated beginning under initial conditions, prevent and suppress material among life-time service and afterwards deteriorated.

Each technical assignment---its solution is included in soft " phase place " and the parameter of impact itself of controlling ultrasonic impact in the acoustics series " oscillatory system-pressure head-processed surface " in synchronous and homophase sonic oscillation process---is passable, according to processed material structure susceptibility, set up velocity of approach and the control of the hunting speed of output place of sonic oscillation system and the different requirements of matching degree.The sole criterion of effective engineering solution of Given task is the required technique effect that obtains degradation inhibiting with minimum energy consumption.This condition determine independently before the ultrasonic impact and among control to the requirement of necessity control degree of the speed of action of material.

Method of the present invention is deteriorated deteriorated with inhibition to prevent by ultrasonic impact protection metal; comprise and providing according to the term of reference of at least a character that affects material and situation and based on the striking energy of the dynamic strength of material; predetermined driving pulse zero hour, be scheduled to phase place and the amplitude of the sonic oscillation of sonic oscillation system near the process on processed surface in oscillatory system.In order to realize this purpose, the method is also by setting the above-mentioned customized parameter of ultrasonic impact in the scope of the maximum value, minimum value and the offset that comprise the resultant velocity vector when impacting beginning, in the ultrasonic impact process behind the processed material of oscillatory system contact according to impact at processed subsurface material structure with based on making oscillatory system requirement of resilience from the processed surface set and change amplitude until ultrasonic impact stops, structural integrity in the surface is provided.

Before both contacts, set amplitude and the phase place of sonic oscillation near the process on processed surface in oscillatory system, so that when the contact beginning, the speed and the energy that impact meet following precondition: keep the middle structural integrity of material in the upper layer, and make the plastic deformation degree on processed surface be no more than saturated level but be enough to be delivered to ultrasonic stress in the processed material and acoustic loss remains in the scope of level that the enough level of the subsequently plastic deformation of appointment is determined to the Q-coefficient by material.

Method of the present invention further comprises the relevant dynamic strength deposit of deformation rate of allowing based on surfacing and its, set oscillatory system near the control degree of the hunting speed in the stage on processed surface, the integrity of the middle structure of material and upper layer is provided thus; Based on processed material susceptibility to the ultrasonic impact effect in turning to the process of designated state, set the sonic oscillation intensity distribution in the ultrasonic impact process, obtain thus described at least character and/or state at the structure and material of processed lower face, wherein hunting speed control degree and sonic oscillation intensity distribution predetermine according to experimental data or by the definite expertise of this task.

In the method for the invention, surfacing keeps the integrity of surfacing to reach wherein structure in the plastic deformation process that is caused by soft impact phase place to be enough to fill up the speed deformation of intergranular defective voids simultaneously.Sealing textural defect border under the power that in the plastic deformation process of the surfacing that the soft power phase place effect of ultrasonic impact causes, produces.Activate defective closing of the frontier surface under the elastic residual stress that can cause in the plastic deformation by processed surfacing.Also can under the pulse of the power that is produced by the impact under the predetermined repetition rate, activate defective closing of the frontier surface.

The activation on defective closing of the frontier surface can be accompanied by oscillatory system lumped mass and distributed mass motion the hunting speed vector and effect, in the phase place of the program setting by control vibration sum velocity, in the sonic oscillation process of oscillatory system end and in the power pulse process that ultrasonic impact causes, be decreased to the oscillatory system end.In shock pulse and ultrasonication process, under the frictional force that the displacement by the defective border causes, activate defective closing of the frontier surface.

The activation on defective closing of the frontier surface is accompanied by in the power pulse action process that is caused by ultrasonic impact the effect through sonic oscillation and the ripple of closed boundary.In the method for the invention, also in the pulse action process of reappearing with the ultrasonic impact repetition rate in phase place that meets material character and effect task, in the rising temperature province that plastic deformation and friction by textural defect border and fragment place cause, activate defective closing of the frontier surface.

By forming and the situation setting of " soft " of the ultrasonic impact that control is determined by task and power phase place, under the static pressure of oscillatory system, power pulse, boundary friction, heating and sonic oscillation and the ultrasonic stress waves in soils, ultrasonic self-diffusion and the annihilation of closed boundary occur.

In a preferred embodiment of the invention, the precipitation of alloy phase is included in the silicon throw out in the Al alloy, and the improved strength of materials that obtains by the control ultrasonic impact is provided.

Be fixed on soft ultrasonic the contact and assault phase with the similar unstable phase of the copper in the Al alloy, thereby prevent from sosoloid, precipitating and preventing deteriorated expansion.

In order to suppress deteriorated or to protect metal deteriorated to prevent, by after its soft phase place, in time the ultrasonic impact strength criterion is realized with the Al alloy in the activation of the similar unfavorable throw out of copper " oppositely " self-diffusion in sosoloid, in this self-diffusion, disadvantageous throw out causes the reduction of structural bond, and it is deteriorated to produce the structural stress centrostigma of hiding and the initiation metal subsequently that are caused by external force; This activation is accompanied by the recovery of strength and ductility of the forfeiture of alloy.

Mutually the activation of migration preferably according to the predetermined variation of ultrasonic impact intensity time since the stdn ultrasonic impact after its soft start occur.This activation preferably is accompanied by the raising of the fatigue resistance that the reduction by the redistribution of potential stress concentration point under the nanostructure level and distribution density causes.

In a preferred embodiment of the invention, on nanometer, microcosmic and the macrostructure fragment aspect of metal, in stdn " soft " phase place of ultrasonic impact and power phase place process subsequently, by ultrasonic impact active material structure in rotation, bending, twinnig, recrystallize, flow, self-acting control in slip, surrender and the timeliness.As the means that improve anti-deterioration, the activation of the segmentation of microscopic level material structure, homogenizing and arrangement is carried out under ultrasonic impact in " soft " and power phase place process subsequently, wherein parameter stdn as being determined by task.Nano level final optimization pass mode as the surface metal structure, decrystallized activation is owing to the process that is caused by ultrasonic impact in " soft " and power phase place process subsequently occurs, wherein based on the experiment that is determined by the task that can make the rapid local heating of metal in the plastic deformation zone and cooling or expert data with standard parameter.The soft power phase place of control ultrasonic impact is to prevent metal at the deteriorated forming core under the initial conditions and to prevent and among its life-time service or afterwards deteriorated of the material that suppresses structure.

In preferred embodiments, (1) protection aluminium alloy is to prevent corrosion spalling and/or (2) recovery and/or to repair because peeling off the character of impaired aluminium alloy.

As described below, shown the effect of method of the present invention with " antagonism " deteriorated inhibition method with comparing, and a series of engineering science solutions and the technology of degradation inhibiting be provided, they use " soft " phase place that high-power ultrasonic impacts during based on structure in affecting the surface and the ultrasonic impact parameter after control " soft " phase place when the processed material character of the processed lower face of impact and situation.

The below is that types of degradation, deteriorated symptom, deteriorated physics, deteriorated generation area and the method for using and transform the processed surface of impact of the present invention and processed material are to suppress deteriorated example.

A kind of types of degradation is mechanical fatigue.The mechanical fatigue symptom comprises fatigue cracking.Fatigue process comprises following phases: at first, since the dislocation desity that improves, the elastic distortion accumulation of lattice; After this, sub microcrack in metallic object, occurs, wherein in the mass slipping of piece independently, obtain the critical position dislocation density; At last, tiny crack grows into macrocrack.Along with the generation of this situation, along tiny crack generation brittle rupture of strong expansion.Mechanical fatigue is the most normal to be appeared in bridge, tunnel, railway, load transportation structure and load lift device, aviation and the transportation (load weld seam, area of stress concentration).Method of the present invention by superpower " soft ultrasonic impact " (PSUI) (it has adaptation on-off time with the synchronous driving pulse of the soft ultrasonic impact of superpower than regulating (O/OTRM)) produce the character that the compensation protection intercepted and recovered damaged material.In order to implement this control of driving pulse on-off time ratio, use pulse width and amplitude adjusted, it starts when needs improve the frequency of synchronizing ultrasound impact, between them, have little (namely to independently the predetermined oscillation inhibition is not enough) time-out, or use the length of independently recovering the transient process of deficiency to vibration.Thus, realize following item: the control of the plastic deformation intensity distribution in each ultrasonic impact process on time and space; The control of the surface parameter under middle structure and crystalline texture rank, its strain deformation state and the penetration depth in existing or possible failure area; The stabilization of phase, the externally lower structure of material in its unstable region of condition (heating, load, environment) and the homogeneity of character.

Another types of degradation is corrosion fatigue.The symptom of corrosion fatigue comprises from the fatigue cracking of surface expansion.The following initiation of fatigue failure process of accelerating by corroding mechanism: the absorption of surfactant, in microfissure, produce wedging effect and cause the hydrogen diffusion of hydrogen embrittlement.Corrosion fatigue is the most normal to be appeared in bridge, tunnel, sea transport, the chemical industry equipment (bearing load weld seam and the area of stress concentration of environment invasion and attack effect).The inclusion contact structures fragment that the invention provides anti-absorption protection and prevent from adsorbing; Improve transport property and the combination loss of inclusion and surfactant and the adsorption surface of absorption, and in the affected area of material or its structure; With optimizing surface, the unrelieved stress in structure and roughness, the upper layer and therefore optimized the anti-adsorptivity (density of material improves in the upper layer) of surfacing wherein.

Another types of degradation is heat and heat-mechanical fatigue.The symptom of heat and heat-mechanical fatigue comprises fatigue cracking.In the fatigue failure process, owing to the mechanical wave stress that hangs down week or high all temperature effectives and cause, parts cyclic deformation.When this situation occurs, may cause heating by the intrinsic primary process of energy harvesting and consumption and the subsidiary reason in the mechanical use procedure.Heat and heat-mechanical fatigue are the most normal to be appeared in heat and Nuclear power plants, Metallurgical Factory's (boiler, smelting furnace), automobile and transportation by railroad and the power operation (parts of braking equipment).The invention provides the heat resistanceheat resistant and the heat-physical disturbance that under initial conditions, improve; Based on the compensation barrier layer that produces distributed unrelieved stress, stress relaxation in heat history and heat-physical disturbance zone and deformation gradient, in the textural defect zone, fill the intergranular space with grain material and in the ultrasonic diffusion of grain boundaries, keep and restorer character; With as reducing time in the braking and the means of thermosteresis, optimize frictional connection spare surface.

Another types of degradation is chemical corrosion.The chemical corrosion symptom comprises uniform dissolution, pit formation and spot corrosion, flaw, crevice corrosion and the corrosion spalling of material.The physics of chemical corrosion comprises that metal-environmental chemistry interacts (gas or liquid), forms from the teeth outwards the reduction of new chemical compound, the strength of materials and the formation of focal point of stress.The negative impact of chemical corrosion is the most normal to be appeared in chemical plant, Nuclear power plants engineering, pipeline transportation (oil tank, pipeline, reactor), aviation and ocean, railway and the Automobile Transportation (shell, skin plating).The invention provides the protection of affected original surface and the recovery of material character; Arrange based on the amplitude variations with " transverter-pressure head-surface " system (TIS) in the PSUI process, the establishment of the layer of compensation of residual compressive stress in decrystallized, the surfacing of modification, surfacing of middle sight and crystalline texture is provided; In the structural failure zone that intergranular corrosion causes in pulse and the ultrasonic diffusion of grain boundaries; The plastic deformation of material, the raising of uniform crystal particles, with grain material fill the intergranular space, in the ultrasonic diffusion of grain boundaries.

Another types of degradation is galvanic corrosion.The symptom of galvanic corrosion comprises that the part (spot corrosion) and the large surface corrosion that are accompanied by dissolving metal destroy.The interactional mechanism of metal-Environmental electrochemistry comprises: anodic process-atoms metal ionization, form hydration in solution ion and the not compensate for electronic in the metal; Electronics is transferred to cathodic process in the process in zone feasible aspect the thermodynamics and kinetics from the anodic reaction district; Oxygenant-depolarizer is applied to the process (reaction of metal ion and electrolyte ion) in cathodic area; Cathodic process-excess electrons is depolarized the agent assimilation and in the cathodic area, provides the thermodynamic condition of recovery process for depolarizer; In this zone, surface geometry is inhomogeneity disintegrates and reduction that upset, structure are strong and the reduction of the strength of materials.Galvanic corrosion is the most normal to be appeared at and contains in oxygen transportation (skin plating, water screw), chemical industry (oil tank, reactor), pipeline, the underground and submerged pipeline.The meaning that suppresses the negative effect of galvanic corrosion according to the present invention comprises: produce galvanic corrosion compensation barrier layer under the initial conditions of material and in the character recovery; The microcosmic of optimizing surface and how much of macroscopic views, the homogeneity of surfacing crystalline texture, as the nanocrystal of the surfacing of the retardance means of anodic process and decrystallized; The establishment in surface plasticity deformation, stress district and the density of material of raising are with the localization of the galvanic corrosion of obstruction surface imperfection; In best surface, in the situation of structure, use PSUI mechanism to form above-mentioned surface appearance.

Another types of degradation is thermal etching.The thermal etching symptom comprises material dissolves and evaporation, and fouling.The physics of thermal etching comprises that the metal of high-temperature induction-environmental chemistry interacts.Thermal etching is the most normal to be appeared in heat and Nuclear power plants, Metallurgical Factory's (boiler, smelting furnace) and chemical plant (reactor).The present invention produces chemical corrosion compensation barrier layer by using PSUI mechanism under the initial conditions of material and in the character recovery; thereby in the applying of protective refractory coating and in the repetition of these operations (if necessary; on layer of scale, and if need to repair surfacing character) middle quality and the raising surface alloying degree of depth optimized.

Another types of degradation is radiation corrosion.The radiation corrosion symptom comprises corrosion pit and crackle.Radiation comprises the dynamic (dynamical) mechanism of action of corrosion process: the Radiolytic effect that is caused and accelerated owing to the ionization of water cathodic process by radiation waterborne; With the damage effect that is interacted and consisted of by elasticity and hot metal surface radiating particle, this causes defective in matallic surface layer and oxide film.These defectives have promoted anodic process and erosion rate have been had far-reaching influence.The most normal the appearing in nuclear power engineering, military installations and the space system of negative effect of corrosion radiation.The method use PSUI mechanism of the surface that impact of the present invention is processed and processed material produces radiation corrosion compensation protection barrier layer under the initial conditions of affected material and in the character recovery, thereby: in the middle optimization quality of applying of protective refractory and radiation paint and the raising surface alloying degree of depth; Surface appearance, middle structure, the microcrystallite structure and material of optimizing the roughness aspect are decrystallized; Stress field and the raising surfacing density favourable with generation.These operate in repetition on the damaged layer provides the radioresistance of surfacing in the aspect of affected original material recovery.

Another types of degradation is corrosion cracking.The corrosion cracking symptom comprises etching crack.Corrosion cracking mechanism comprises: the solution Anion-adsorption on dislocation movably and other textural defect, the fracture that this has reduced surface energy and has promoted the atomic linkage of metal; Because crack nucleation appears in the wedge of surfactant when it is adsorbed in the microfissure on the metallic surface.High crack growth rate in this case is to be caused by the anode dissolution that metal accelerates in the crackle substrate, and wherein stress-deformation state is usually concentrated by tensile stress and determined.Corrosion cracking is the most normal to be appeared in chemical plant, nuclear power engineering and the pipeline transportation (oil pipe, pipeline, pumping installation, reactor).The method of corrosion cracking that prevents of the present invention uses PSUI mechanism producing the compensation protective barrier layer that prevents that etching crack from forming under the initial conditions of material and in its character is recovered, thereby: optimize quality, the binding property that is applied to possible or actual impaired lip-deep protective coating or improve its alloying degree of depth, and under the best or specified conditions of middle structure, in the enhancing on surface or modification, in the surface, bring out favourable stress to predetermined depth; Change structure and create the stress-deformation state of material structure in case make reduce the strong solution negatively charged ion on movably dislocation and other textural defect of surface energy and reduction atom absorb impossible; The crack nucleation that structure and preventing is caused by the wedge of surfactant when it is adsorbed in the microfissure on the metallic surface in the optimizing surface; The surface of structure produces the stress field in having the best, and its magnitude and the degree of depth are enough to prevent the high crack growth rate that caused by the anode dissolution that metal accelerates in the crackle substrate, and wherein stress-deformation state is usually concentrated by tensile stress and determined.

Another types of degradation is hydrogen embrittlement.The hydrogen embrittlement symptom comprises reduction and the brittle crack of strength property.Hydrogen embrittlement mechanism comprises: atomic hydrogen infiltrates space, hole and other lattice imperfection; Hydrogen changes into atomic hydrogen, and this causes high pressure; Atomic hydrogen is adsorbed on parts surface and the subsurface defect, forms chemical compound with metal and impurity; With reduction metallic surface energy and anti-brittle rupture.Hydrogen embrittlement is the most normal to be appeared between Metallurgical Factory and engineering truck, in pipeline (welded construction, electroplanting device), petrochemical plant (reactor) and the aviation (shell).The method of hydrogen embrittlement that prevents of the present invention uses PSUI mechanism to be used for: strengthen surface alloying quality, bond strength and electrolytic coating density; The surface of structure produces the stress field in having the best, and its magnitude and the degree of depth are enough to prevent that the strength property that is caused by the infiltration of atomic hydrogen in space, hole and other lattice imperfection from reducing and brittle crack forms; Prevent that hydrogen from changing into molecular hydrogen, this produces pressure between high segment; Prevent that atomic hydrogen is adsorbed on material surface and the subsurface defect, form chemical compound with metal and impurity, this reduces metallic surface energy and anti-brittle rupture.

Another types of degradation is Liquid Metal Embrittlement.The symptom of Liquid Metal Embrittlement comprises the reduction intensive property and produces brittle crack.Liquid Metal Embrittlement mechanism comprises: molten metal absorption is infiltrated in the pre-failed areas of solid metal; The reduction of surface energy and anti-metal fracture in the affected area.Liquid Metal Embrittlement is the most normal to be appeared in Metallurgical Factory's (electroplate and make).The reduction that of the present invention prevent or the method for " reparation " Liquid Metal Embrittlement uses PSUI to produce from the teeth outwards structure and stress field in the best, its magnitude and the degree of depth are enough to prevent that strength property from reducing, the pre-failed areas of solid metal, surface energy and anti-metal fracture are infiltrated in the formation of brittle crack, molten metal absorption.

Another types of degradation is to corrode.The erosion symptom comprises the variation of surface undulation.Eater Neo-Confucianism comprise since main body and fluxion, gaseous environment or its particle of carrying secretly contact or owing to solids make solids break away from affected body surfaces to the bump on affected surface.Corrode the most normal appearing in pipeline transportation (pipeline, pumping device), aviation (turbine), sea transport (water screw), rocket and the guided missile (shell).The surface that weathers of the present invention prevent or restoration methods uses PSUI to produce lip-deep optimum density, roughness, middle structure and stress field, its magnitude is enough to prevent with the degree of depth because the contacting or make solids break away from affected body surfaces owing to solids clash on affected surface of main body and fluxion, gaseous environment or its particle of carrying secretly.

Another types of degradation is creep.The creep symptom is included in and forms tiny crack and hole (microvoid) on crystal boundary and the substructure layer.Creep mechanism comprises: slide and mobile (displacement diagram); Twinnig; The bending of slip plane; Stratification; The rotation of crystal grain and relative movement; The rotation of mosaic block and relatively moving; Poligonization; Diffusion plasticity; Recrystallization mechanism; With defect and the structure deteriorate on microcosmic and macroscopic aspect.Creep is the most normal to be appeared at hot and Nuclear power plants, petrochemical industry and aviation (at high temperature structure, reactor body and the turbine blade of operation).Of the present invention preventing uses PSUI to obtain optimum density with the method for " reparation " creep, the crystal grain of middle constructional aspect and filler size and at surface and subsurface compression macrostress and microstress, its magnitude and the degree of depth are enough to prevent form tiny crack and hole (microvoid) in crystal boundary and substructure, slide and mobile (based on displacement diagram), twinnig, the bending of slip plane, stratification, the rotation of crystal grain and relative movement, the rotation of mosaic block and relatively moving, poligonization, diffusion plasticity, recrystallize, with defect and the structure deteriorate on microcosmic and macroscopic aspect.

Another types of degradation is that microstructure is deteriorated.The deteriorated symptom of microstructure comprises the reduction of strength of materials character.The microstructure degradation mechanism is included in little surface of expanding in the deformable body and absorbs molecule (restructuring effect) from environment, and in the situation that does not significantly change microstructure take transform unstable phase as cost makes disadvantageous metallographic phase condition stabilization (timeliness) in time.Microstructure the most normal deteriorated appearing in power station, refinery's (skeleton construction), pipeline, sea transport and the aviation (main body, shell).Of the present invention preventing produces best density of material, the middle structure on the material surface with the deteriorated method of " reparation " microstructure based on use PSUI, with make lip-deep plastic deformation and the stdn of stress field, its magnitude and the degree of depth are enough to prevent that by the deteriorated strength of materials reduction of performance that causes of microstructure the deteriorated little surface expanded in the deformable body that can be included in of this microstructure absorbs molecule (restructuring effect) from environment; And/or in the situation that does not significantly change microstructure take transform unstable phase as cost makes disadvantageous metallographic phase condition stabilization (timeliness) in time.

Another types of degradation is Irradiation embrittlement.The symptom of Irradiation embrittlement comprises being increased sharply of brittle cracking and yield strength.The physics of Irradiation embrittlement comprises that neutron current makes knocking out or produce displacement cascade (this depends on the energy of neutron transfer in the atoms metal) in metal lattice, and this produces the material body (volumes) with high hole concentration that the zone that had the interstitial atom density of raising along the edge centers on.Irradiation embrittlement is the most normal to be appeared in nuclear power engineering (reactor), space system and the military installations (Missile Body shell).Of the present invention prevent or the method for " reparation " Irradiation embrittlement uses PSUI by surface plastic deformation and the stdn of the stress field optimum density and the middle structure that obtain processed material up and down, its magnitude and the degree of depth are enough to, in the situation that yield strength is increased sharply, prevent from forming the brittle crack that is caused by the displacement of metal lattice Atom or displacement cascade (under neutron current) (this depends on the energy of neutron transfer in the atoms metal), and prevent from subsequently forming the high hole concentration that the zone of the interstitial atom density that is had raising along the edge centers on.

Another types of degradation is to peel off.Peel off formation and loss of strength that symptom comprises the metallic surface corrosion spalling and is accompanied by focal point of stress.The physics of peeling off comprises the synergistic effect of corrosion and hydrogen embrittlement.Peel off the most normal appearing in the aeronautics.The method that prevents or suppress ongoing corrosion spalling of the present invention is based on using PSUI, its level and time parameter meet the requirement of the integrity of optimum density through testing the processed material of definite acquisition and guaranteed wherein structure, with partial points heating and the heat dissipation speed that dissipates from this plastic deformation zone, plastic deformation itself with the formation of the stress field about on processed surface and the requirement of normalization condition, its magnitude and the degree of depth are enough to:

-in special these failure areas that caused by the synergistic effect of corrosion and hydrogen embrittlement, prevent formation and the loss of strength of metallic surface corrosion spalling and focal point of stress,

-prevent from forming and cause the mutually unsettled of component precipitation (thereby producing the structure band content and the strength of materials that reduces), Cu for example,

The corrosion cracking of the self-diffusion at-activation structure segment boundaries place and elimination grain boundaries,

-when its border of sealing and activation self-diffusion process, eliminate structure both macro and micro defective, for example the intergranular of hole and other type is interrupted,

-recovery of sedimentary counter diffusion and stable phase is provided,

-precipitation of this zone interalloy element, the raising of its concentration and density and the intensity of material is provided,

-guarantee compensation, the redistribution and lax of construction machine stress in its concentrated area of being caused by the throw out from the sosoloid of unstable phase,

-form on this basis superfine crystal particle structure, its raising and erosion resistance thereof decrystallized, the strength of materials.

The concrete engineering that above describes in detail is learned the specific embodiment that solution can change into metal degradation inhibiting method of the present invention.The below describes in detail by the technique effect that uses the effect of the method for ultrasonic impacts to realize at various materials of developing.The below also describes the experimental studies results of this effect and condition and the effect that realizes in detail.More particularly, the below describes ultrasonic impact according to the present invention in detail to the inhibition of metal degradation phenomena.

Therefore, in cast iron, the material result that realizes is the life-span of the prolongation of the automobile brake drum that is made of cast iron and dish.The result is presented among Figure 52-53.Figure 52 has shown the microhardness distribution, and Figure 53 has shown residual stress distribution.Be used for realizing that the UIT condition optimization of this material result is as follows: f-27kHz; A-30 μ m; Pressure-21kg; Pressure head-6.35x25mm, R5.5mm; Dia.-419mm; Rot.-190RPM; The 1st road; Charging-0.8mm/min.; The 2nd road: charging-0.4mm/min.The microhardness of the introducing of this material effect by high-level stress, upper layer improves and prevents that the destruction that usefulness and processing by microstructure cause from realizing.

The corrosion strength that improves according to the present invention by UIT another material result in cast iron, particularly by the castiron water cast-iron pipe of VCh45-5 type ANSI/AWWA C151/A21.51-96.The result is presented among Figure 54-56.More particularly, Figure 54 has shown the structure of untreated sample under 100 micrometer depth, and Figure 55 has shown the structure of sample under 100 micrometer depth that UIT processes, Figure 56 shown by with the not contrast by UIT sample that process and that in tap water, test.The UIT condition optimization of this material effect is as follows: f-44kHz; A-18 μ m; Pressure-5kg; Pressure head-5x25mm, R5mm; Dia.-230mm; Rot.-16RPM; Charging-0.25mm/min.This material effect by under strong stdn plastic deformation, change surface layer structure, the inhibition of the surface imperfection of structure deteriorate realizes by the generation in stress zone and in use causing.

The material result that realizes at steel is the fatigue resistance of the raising of welded sample in Weldox 420 steel.The result is presented among Figure 57.As follows for the UIT condition optimization that obtains this material result: f-27kHz; The maximum 900W of P-; A-30 μ m; Pressure-5kg; Ultrasonic impact time length-1.2-2msec.This material result realizes in the structural modification of area of stress concentration by introducing, stress concentration reduction, ultrasonic plastic deformation and the processed material of high-level stress.In guaranteeing to use the PSUI protection structure with prevent from using and surperficial set-up procedure in processing induce destroy and sonic oscillation condition, pressure and pressure head size that operation destroys between, set up preference relation through experiment.

Another material result that realizes in steel is the fatigue resistance of the raising of welded sample in Weldox 700 steel.The result is presented among Figure 58.As follows for the UIT condition optimization that obtains this material result: f-27kHz; The maximum 900W of P-; A-30 μ m; Pressure-5kg; Ultrasonic impact time length-0.8-1.2msec.This material result realizes in the structural modification of area of stress concentration by introducing, stress concentration reduction, ultrasonic plastic deformation and the processed material of high-level stress.In guaranteeing to use the PSUI protection structure with prevent from using and surperficial set-up procedure in processing induce destroy and sonic oscillation condition, pressure and pressure head size that operation destroys between, through the experiment opening relationships.

Another material result that realizes in steel is the corrosion-fatigue strength that improves in the 45Mn17A13 steel.The result is presented among Figure 59.As follows for the UIT condition optimization that obtains this material result: f-27kHz; The maximum 900W of P-; A-30 μ ra; Pressure-5kg; Ultrasonic impact time length-1.5-2msec.This material result is by introducing high-level stress and structural modification realizes in processed surface and processed material.Guarantee to use ultrasonic impact of the present invention using and surface treatment process in the protection between sonic oscillation condition, pressure and the pressure head size of structure, through the experiment opening relationships.

Another material result that realizes in steel is the shock strength of the raising of Bridge Steel 10CrSiNiCu.The result is presented among Figure 60.As follows for the UIT condition optimization that obtains this material result: f-27kHz; The maximum 900W of P-; A-30 μ m; Pressure-5kg; Ultrasonic impact time length-1.2-1.7msec.This material result by block structure in the arrangement of nanometer aspect be enough to realize in the establishment in the stress zone of structure deteriorate by ultrasonic impact (its stdn as optional the decision) and in being hindered during processed material by the quasistatic of operating physical force initiation and Dynamic Loading subsequently.

Another material result that realizes in steel is the grain refining in high-strength steel SUJ2 and S33C.The result is presented among Figure 61.Be used for realizing that the UIT condition optimization of this material result is as follows: f-27kHz; A-25,30 and 33 μ m; NI80; Pressure-20kg; Pressure head-6.35x25mm; Dia.-5mm; Rot.-500RPM; Ultrasonic impact time length-1.5-1.6msec.This material result realizes in the arrangement of nanometer aspect and the inhibition of middle structure deteriorate by strong ultrasonic plastic deformation and the microstructure of processed material.

Another material result that realizes in steel is to obtain " white layer " in the 10Mn2VNb of main pipe line steel weld and in the sample of high-strength steel SUJ2.More particularly, Figure 62 has shown the weld of 10Mn2VNb steel, and Figure 63 has shown the sample of SUJ2 steel.Be used for realizing that the UIT condition optimization of this material result is as follows:

For the 10Mn2VNb steel: f-27kHz; The maximum 900W of P-; A-30 μ m; Ultrasonic impact time length-0.8-12msec.

For the SUJ2 steel: f-27kHz; A-25,30and 33 μ m; NI80; Pressure-20kg; Pressure head-6.35x25mm; Dia.-5mm; Rot.-500RPM.

This material result by the strong ultrasonic plastic deformation under the stdn ultrasonic impact of surfacing under high deformation loading rate, in the phase change region local heating and realize from the rapid heat extraction of shock zone.

Another material result in steel is by the impact realization of UIT on the welding metal crystallization among the welding carbon ship steel 10CrSiNiCu, and it comprises: the dendritic structure in (1) untreated weld seam (before the UIT) is much thicker than the weld seam of processing (after the UIT); (2) mainly be preferably to have more compact grained crystalline-granular texture in the weld seam that UIT processed; (3) length of the dendrite in the untreated weld seam before the UIT after than UIT and wide and in thicker intergranular layer.This effect is presented among Figure 64-65.More particularly, Figure 64 has shown the welding without UIT, and Figure 65 has shown the welding under UIT.Be used for realizing that the UIT condition optimization of this material result is as follows: f-27kHz; A-30 μ m; Pressure-20kg; Pressure head-6.35x25mm; Ultrasonic impact time length-1.5-2msec.This material result realizes by enhancing diffusion process and metal recrystallize under the effect of ultrasonic wave, sound stream, acoustic pressure and cavitation (these are by pressure head sonic oscillation initiation synchronous with the carrier oscillation of sonic oscillation system in the ultrasonic impact process).

Another material result that affects the structure of material and situation realizes by the UIT of sintered powder steel.This has strengthened the mechanical properties of steel sample, and this sample contains 0.4%C, 0.85%Mo, and all the other are Fe, comprising: the density of (1) maximum 4.9% raises; (2) maximum 32% intensity raises.The constructional aspect of sintered specimen before UIT and after UIT is presented at respectively among Figure 66-67.Be used for realizing that the UIT condition optimization of this point is as follows: f-27kHz ,-A-28 μ m; NI64; Pressure-17kg; Pressure head-6.35x25mm; Charging-400mm/min.; Intersection charging-0.5mm/travel; Static state pressurization under the 0.5YS level; Ultrasonic impact time length-1.2-2msec.This material result by surfacing strong ultrasonic plastic deformation and the activation of the diffusion process that in the ultrasonic impact process, caused by ultrasonic wave realize.

The material result that realizes in aluminium alloy by UIT of the present invention is the safe range of stress of the raising 21% of the sample made by 6061 T6 alloys, and the safe range of stress of the raising 32% of the structure suitable with the welding point of general.The result is presented among Figure 68.Be used for realizing that the UIT condition optimization of this material result is as follows: f-27kHz; The maximum 900W of P-; The maximum 30Um of A-; Processing speed-per 2 road 1.2sec./cm is namely for per one 0.6sec./cm of overlapping weld; Ultrasonic impact time length-1.2-1.7msec.Introducing, the stress concentration of this material result by high-level stress reduce and create prevent from directed plastic deformation zone, forming in the physical barrier layer of textural defect and the stress corresponding with defect level realize.

Another material result that realizes in aluminium alloy is that the high-cycle fatigue strength of the raising of weld seam among the aluminium alloy AA5083 (and AlMg4.5Mn) is about 80% for 8 millimeters overlapped points with the sample with vertical tie point.The result is presented among Figure 69-79.More particularly, Figure 69 has shown the S-N curve of 8 millimeters samples with vertical tie point, and Figure 70 has shown the S-N curve of 8 millimeters samples of overlapped points.Be used for realizing that the UIT condition optimization of this material result is as follows: f-27kHz; The maximum 900W of P-; The maximum 30 μ m of A-; Ultrasonic impact time length-1.2-1.7msec.Introducing, the stress concentration of this material result by high-level stress reduces and suppresses possible middle structure deteriorate by ultrasonic recrystallize in sosoloid and the ultrasonic diffusion that activates grain boundaries in ultrasonic impact process according to the present invention and realize.

Another material result that realizes in aluminium alloy is nearly surface, especially the inhibition of the casting porosity under maximum 2.5 mm depths, therefore and prolong the casting tire, the alloy life of the doughnut of especially being made by AlSi7Mg, AlSi9Mg and AlSiIlMg.The result is presented among Figure 71-72.Be used for realizing that the UIT condition optimization of this material result is as follows: f-27kHz; Charging-400mm/min.; Intersection charging-0.5mm/travel; Pressure-15kg; A-30 the 1st road: pressure head-6.35x25mm, R5.5mm; The 2nd road: Pin-9.05x25mm, R10mm; Ultrasonic impact time length-1.2-1.7msec.This material result by the strong plastic deformation of the processed nearly superficial layer of material, the defect border that is space or form of discontinuity in material sealed under ultrasonic impact ultrasonic diffusion and on the middle fault of construction in standardization plastic deformation zone and at standardization ultrasonic impact of the present invention and be accompanied by the effect that its impact on structure produces (this especially by ultrasonic stress wave in the material because of ultrasonic impact deformation spread process in the anti-deformation behavior that reduces cause) inhibition of the lower compression corresponding with the plastic deformation degree realizes.

Except the intensity of the raising of processed material, another material result that realizes in aluminium alloy by UIT of the present invention is the shock strength of the material that keeps processed, particularly in the manufacturing of the casting tire of being made by alloy A lSi7Mg, AlSi9Mg and AlSi11Mg.The result is presented among Figure 73-74.More particularly, Figure 73 has shown the shock strength on the sample of the breach with enhancing, and Figure 74 has shown the shock strength on the sample that downcuts from the tire that strengthens.UIT and ultrasonic impact mechanical workout (UIM) condition make it possible to the shock strength in the fixing zone that is loaded the strong plastic deformation that causes by the impact under the original material aspect.In the zone of action of the ultrasonic stress waves in soils that is caused by ultrasonic impact, shock strength improves 12%.Be used for realizing that the UIT condition optimization of this material result is as follows: f-27kHz; Charging-400mm/min.; Pressure-15kg; Pin-9.05x25mm, RO.25mm; Wedge 44 °; Condition 1:A-10 μ m; Condition 2:A-20 μ m; Condition 3:A-30 μ m; Ultrasonic impact time length-1.2-1.7msec.Additional UIT condition is: f-27kHz; Pressure head-6.35x25mm, R25mm; The UIT condition: The 1st road: A-20 μ m and The 2nd road: A-12 μ m; UIM condition: V-18m/min.; Charging-0.5mm/rev.; Pressure head-6.35x33mm, R25mm; The 1st road: pressure-15kg and A-22 μ m; The 2nd road: pressure-7kg and A-12 μ m; Ultrasonic impact time length-1.2-1.7msec.Because in UIM and UIT process, may under strong plastic deformation structural distortion occur, therefore this may cause the dislocation retardance and form other defective in the crystal grain rank in processed material, specified this situation according to the present invention, wherein behind the UIT of focal point of stress, the shock strength of Charpy bay directly depends on specimen size, i.e. the relation of deformation and volume unstrained material.Explain that charpy test is pendulum type list blow shock test, the sample that wherein will usually carve otch is supported on two ends and the impact by the whereabouts pendulum at otch as simply supported beam, and dynamic stress concentration point place disconnects.The energy that use to absorb as the pendulum by subsequently raise the shock strength that calculates or notch toughness module (after the impact that makes sample fracture) in addition, but the shellfish value directly is subjected to the impact of structure in the otch, and it is controlled by the plastic deformation in ultrasonic impact mechanism of the present invention with by the ultrasonic stress waves in soils stdn of its initiation according to the present invention.

Another material result that in aluminium alloy, realizes by UIT of the present invention specifically the silicon inclusion from AlSi ₁₁Precipitate in the sosoloid of Mg alloy, this is alloy inclusions and has improved the strength of materials.This effect is presented among Figure 75-77.More particularly, Figure 75 has shown untreated sample structure; Figure 76 has shown the silicon throw out on the sample that UIT processed; Figure 77 has shown that the microhardness in the degree of depth of untreated sample and UIM sample distributes, and it clearlys show that owing to the precipitation of silicon inclusion in this layer, the surface of processing and the material of processing are in the raising of little intensity at least 2 mm depth places.Be used for realizing that the UIT condition optimization of this material result is as follows: f-27kHz; V-18m/min.; Charging-0.5mm/rev.; Pressure head-6.35x25mm, R25mm; The 1st road: pressure-15kg and A-22 μ m; The 2nd road: pressure-7kg and A-12 μ m; Ultrasonic impact time length-1.2-1.7msec.This material result makes upper layer strengthen to realize by UIM of the present invention by the structural changes by wherein generation.In upper layer, by the two-phase condition of original texture (α+eutectic (the more solid-state eutectic structure of α+Si)+Si) form (α+Si)+Si.This process also is accompanied by the silicon inclusion and has also substantially embodied because silicon precipitates and the target capability of REINFORCED Al-Si alloy in nearly upper layer to surface transport under ultrasonic impact.

Another material result that realizes in aluminium alloy by UIT/UIM of the present invention is the recovery of the character of 2024-T351 alloy behind corrosion spalling.Behind the UIT according to the present invention, the yield strength of peeling off sample improves 33% (comparing 19% with untreated not exfoliation material improves), final strength improves 24% and (compares with untreated not exfoliation material, behind UIT/UIM, raising reaches the typical intensity of this material in measuring accuracy).The result is presented among Figure 78-79.Be used for realizing that the UIT condition optimization of this material result is as follows: f-36kHz; Pressure head-5x17mm, R25mm; A-18 μ m; NI64; Pressure-3kg; Charging-400r π m/min.; Intersection charging-0.5mm/travel; Ultrasonic impact time length-1.0-1.3msec.This material result spreads to realize by the ultrasonic impact of grain boundaries.

Another material result that realizes in aluminium alloy by UIT of the present invention is 3.2 times raising and 2.9 times the raising in the heavy corrosion sample the sample of slight corrosion of the cycle lie of the sample of being made by the 7075-T6 alloy that cuts from the aircraft wing shell plating.Figure 80 shows that UIT of the present invention is on the impact of the fatigue resistance of sample with different extent of corrosions.Be used for realizing that the UIT condition optimization of this material result is as follows: F-36kHz; Pressure head-5x17mm, R25mm; A-20 μ m; NI64; Pressure-3kg; Charging-400mm/min; Intersection charging-0.5mm/travel; Ultrasonic impact time length-1.0-1.3msec.UIT of the present invention has changed crack nucleation mechanism.Therefore, for the corrosion sample without UIT, crackle is by the intergranular crack forming core on the interface of corrosion area and substrate; For according to the present invention through the slight corrosion sample of the UIT of these parts, crackle is forming core not, this is interpreted as the mechanical close of crystal boundary and the subsequently ultrasonic diffusion between them in the intergranular corrosion destroyed area under strong ultrasonic plastic deformation.

Another material result that realizes in aluminium alloy by UIT of the present invention is the more fine structure (on average from 16.52 nanometers to the 8-10 nanometer) that 2024-T351 alloy cold-reduced sheet is compared with original state.The result is presented among Figure 81-82.More particularly, Figure 81 shown UIT process before structure in the upper layer, Figure 82 has shown the thinner crystalline-granular texture by the UIT refinement.Be used for realizing that the UIT condition optimization of this material result is as follows: f-36kHz; Pressure head-5x17mm, R25mm; A-15 μ m; NI64; Pressure-3kg; Charging-1000mm/min.; Intersection charging-0.5mm/travel; Ultrasonic impact time length-0.9-1.2msec.This material result of grain refining is caused by underlying cause: because additional deformation forms high dislocation density and twin structure; Form microstrip structure; Microstrip structure is subdivided into sub-micron grain; Subgrain is further broken into pieces in order to wait axle.

By another material result, the especially cold-reduced sheet of 2024-T351 alloy that UIT of the present invention realizes in aluminium alloy, it is the appearance of the wide little band of throw out migration and 10-15 nanometer.This be accompanied by inferior fine grained structure improve under nano level from alignment processes and in upper layer in anti-machinery and the corrosion failure of structure.Therefore.The raising that two effects that produce owing to UIT of the present invention are microhardnesss in the upper layer and the therefore raising of the static strength of material, with pass through throw out, be that the condition of improving fatigue strength is created in the reduction of the distribution density of structural stress centrostigma, and the raising of structural uniformity in the upper layer.This effect is presented among Figure 83-85.More particularly, Figure 83 has shown the microhardness distribution, and Figure 84 has shown that UIT of the present invention processes surface layer structure before, and Figure 85 has shown the little band in the UIT sample.Use energy dispersed light spectrometry (EDS) to check that throw out shows that throw out is rich in Al, Cu, Fe, Mn and Si.But sedimentary density it is found that on the surface of UIT sample and nearly surface and shows minimum value.Compare with " only being rolled into " state and to show that the throw out behind the UIT shows the size of reduction, their density shows maximum value in these bands of a spectrum simultaneously.By the comprehensive comparison of above-mentioned observation, on structural level, potential stress concentrations distribution density roughly reduces.This can be regarded as improving the prerequisite that the material antifatigue is destroyed the formation ability.Be used for realizing that the UIT condition optimization of this material result is as follows: f-36kHz; Pin-5x17mm, R25mm; A-18 μ m; NI64; Pressure-3kg; Charging-400mm/min.; Intersection charging-0.5mm/travel; Ultrasonic impact time length-1.0-1.3msec.This material result is by the geometric dynamic recrystallization process implementation, and wherein high-energy and high-temperature can reach critical level and therefore cause the throw out migration.Under any circumstance, this effect all is accompanied by the distribution of stdn effect, local heating, heat abstraction, the ultrasonic stress waves in soils of stdn of ultrasonic impact and the stdn of the Plastic Deformation deformation that causes thus.

The material result that realizes in bronze by UIT of the present invention is the raising of corrosion fatigue strength, particularly Cu ₃Bronze water screw (BrAl ₉Fe ₄Ni ₄).The result is presented at Figure 86-87.More particularly, Figure 86 shows the corrosion failure on the untreated sample surfaces, and Figure 87 has shown the sample surfaces behind the UIT.Be used for realizing that the UIT condition optimization of this material result is as follows: f-27kHz; P-900W; The maximum 30 μ m of A-; Pins-3x20mm, R3mm.The introducing of this material result by high-level stress, surface layer structure modification, in the ultrasonic diffusion of closing of the frontier place of textural defect (such as hole), prevent from destroying and the middle structure deteriorate that suppresses microscopic level and macro-level realizes.

Because crackle of different nature consists of the metal the most general deteriorated final sign of main Types, UIT begins crackle and the concrete grammar of expanding dynamic (dynamical) impact comprises:

(a) have the roughness that for example is not more than 0.5 micron and " very " the smooth surface that is induced to the residual compressive stress of maximum 0.7 millimeter less degree of depth, the beginning that wherein this class surface can " for a long time " delayed cracking, and after beginning, may have quite rapidly crack propagation, and suppress by the UIT technology of the invention described above;

(b) for example have 0.5 micron and larger roughness, complete middle structure and be induced to the smooth surface of the stress of maximum 1.5 millimeters middle deep, it can reach sizable degree of depth, but be not less than in the high pressure stress field of 0.7-1.5 millimeter, realize material long crackle is begun and begins after the resistivity of expansion;

(c) have the close grain in complete surperficial lower structure (tiny area damage may reach be not more than 0.003 millimeter the degree of depth), the sub-surface layer and be induced to the smooth surface of the stress of maximum 2.5 millimeters larger degree of depth, it produces higher material cracking resistance line beginning property and slow down crack propagation after beginning in fine grained structure zone and stress field;

(d) have close grain and the non-crystal structure in complete surperficial lower structure (tiny area damage may reach be not more than 0.008 millimeter the degree of depth), the nearly upper layer and use controlled ultrasonic impact to be induced to smooth surface for the stress of given material full depth, it produces, and higher material cracking resistance line beginning property is also slowed down crack propagation in close grain and/or non-crystal structure zone and continuation crack retardation in stress field (yield strength of the material that it is basic and processed contrasts).

In addition, the crackle of beginning is " fixed " and the expansion of the following effect delay fatigue crackle by IT of the present invention:

(a) diffusion of crack edge connects;

(b) (crackle preservation) in the residual compressive stress district flooded in the crack propagation district;

(c) remove the matallic surface layer (being similar to grinding) of cracking until int metal.

The above-mentioned materials effect realizes by control ultrasonic impact parameter in its soft power phase place process.In addition, the main standard of setting the ultrasonic impact parameter is the concrete engineering task, and it has determined the requirement to the control degree.In addition, set the ultrasonic impact parameter based on experiment or expert data.Thus, according to the present invention, the ultrasonic impact parameter, especially sum velocity, striking energy, the repetition rate syzygies when impacting beginning hit the control degree that time, impact amplitude closes phase place and determined by specific tasks according to experiment or expert data, wherein sets these parameters with 5% to the dispersity of random value based on concrete technical requirements and actual result.

The result that the above describes in detail has confirmed to use ultrasonic impact of the present invention to suppress to cause the hi-tech effectiveness of the technology (developing according to the present invention) of the deteriorated phenomenon of metal and deteriorated (if this occurs) own in mechanical and structure use procedure.

It being understood that can be on material independent or prevent by described engineering science solution in combination or suppress any above-mentioned types of degradation or deteriorated symptom, thereby at least one material result that realizes any required technique effect or required by task is provided.For example, can solve independently deteriorated to realize a technique effect or can and/or corrode in conjunction with solving to realize further technique effect with for example heat cracking based on corrosion cracking.Therefore, different data elements can exchange to realize different result or technique effect for different task.

Those skilled in the art can find out, can make various modifications in above-mentioned specification sheets scope.This class in those skilled in the art's ability is revised a formation part of the present invention and is included in claims.

Claims (62)

1. one kind prevents that metal is deteriorated and suppresses deteriorated method by the ultrasonic impact under striking energy, and described striking energy comprises by the task decision of at least a character that affect material or situation and based on the dynamic strength of material:

The moment that predetermined driving pulse begins, during oscillatory system is near processed surface phase place and the amplitude of the sonic oscillation of sonic oscillation system end, so that the middle structural integrity on surface to be provided, comprise maximum value, minimum value and the offset of the resultant velocity vector when impacting beginning in a scope; With

According to the processed subsurface material structure of impact with based on the requirement to the resilience from the described processed surface of described oscillatory system, set during the ultrasonic impact after described oscillatory system contacts described surface and the change amplitude, until described ultrasonic impact stops

It is characterized in that, during the process of described oscillatory system near described surface, before both contacts, set amplitude and the phase place of sonic oscillation, so that when the contact beginning, the speed of described impact and energy meet the precondition that keeps the middle structural integrity of material described in the upper layer, wherein the plastic deformation on processed surface is no more than its saturated level but is enough to ultrasonic stress is delivered in the described material, and acoustic loss remains on the subsequently plastic deformation of appointment enough but be not more than in the scope of the value that the Q-coefficient by described material determines.

2. one kind prevents that metal is deteriorated and suppresses deteriorated method by the ultrasonic impact under striking energy, and described striking energy comprises by the task decision of at least a character that affect material or situation and based on the dynamic strength of material:

The moment that predetermined driving pulse begins, during oscillatory system is near processed surface phase place and the amplitude of the sonic oscillation of sonic oscillation system end, so that the middle structural integrity on surface to be provided, comprise maximum value, minimum value and the offset of the resultant velocity vector when impacting beginning in a scope; With

According to the processed subsurface material structure of impact with based on the requirement to the resilience from the described processed surface of described oscillatory system, set during the ultrasonic impact after described oscillatory system contacts described surface and the change amplitude, until described ultrasonic impact stops

Described method also comprises:

The dynamic strength deposit that the deformation rate of allowing based on surfacing and its is relevant is set in described oscillatory system near the control degree of the hunting speed in the stage on described surface, and the integrity of the middle structure of described material and upper layer is provided thus; With

Based on described processed material susceptibility to the ultrasonic impact effect in turning to the process of designated state, set the sonic oscillation intensity distribution in the ultrasonic impact process, this distribution is enough to obtain the described at least a character at material structure and the material of lower face

Wherein, described hunting speed control degree and sonic oscillation intensity distribution are predetermined by described task according to experimental data or expertise.

3. method according to claim 1 also comprises:

The dynamic strength deposit that the deformation rate of allowing based on surfacing and its is relevant is set in described oscillatory system near the control degree of the hunting speed in the stage on described surface, and the integrity of the middle structure of described material and upper layer is provided thus; With

Based on described processed material susceptibility to the ultrasonic impact effect in turning to the process of designated state, set the sonic oscillation intensity distribution in the ultrasonic impact process, this distribution is enough to obtain the described at least a character at described material structure and the material of described lower face

Wherein, described hunting speed control degree and sonic oscillation intensity distribution are predetermined by described task according to experimental data or expertise.

4. each described method according to claim 1-3, it is characterized in that, during the plastic deformation in the soft impact mutually predetermined according to described task, described material surface is with integrity and wherein speed and the energy deformation of structure on the described surface that is enough to fill up the intergranular defective voids and keeps simultaneously described material.

5. each described method is characterized in that according to claim 1-3, and under the effect of the power that produces in the described surface plasticity deformation process of the described material that the effect by the soft power phase place of described ultrasonic impact causes, the textural defect border is closed.

6. each described method is characterized in that according to claim 1-3, activates defective closing of the frontier surface under the elastic residual stress that the plastic deformation by the described surface of described material causes.

7. each described method is characterized in that according to claim 1-3, under the effect of the power pulse that is produced by the impact under the predetermined repetition rate, activates defective closing of the frontier surface.

8. each described method according to claim 1-3, it is characterized in that, during the sonic oscillation of the described oscillatory system end in the phase place corresponding with the power pulse that obtains vibration sum velocity and caused by described ultrasonic impact, the activation on defective closing of the frontier surface be accompanied by the hunting speed vector of the motion of oscillatory system lumped mass and oscillatory system distributed mass and effect, it is terminal that it is lowered to described oscillatory system, wherein, described vibration sum velocity and power pulse are predetermined according to described task.

9. each described method is characterized in that according to claim 1-3, during shock pulse and ultrasonication, under the effect of the frictional force that the displacement by the defective border causes, the activation on defective closing of the frontier surface occurs.

10. each described method is characterized in that according to claim 1-3, and the activation on defective closing of the frontier surface is accompanied by during the power pulse action that is caused by described ultrasonic impact the effect through sonic oscillation and the ripple of closed boundary.

11. each described method according to claim 1-3, it is characterized in that, during the pulse action that in the controlled phases that is determined by material character and described task, reappears with the ultrasonic impact repetition rate, in the rising temperature province that plastic deformation and friction by textural defect border and fragment place cause, activate the defective closing of the frontier.

12. each described method is characterized in that according to claim 1-3, under the effect of static pressure, power pulse, boundary friction, heating, sonic oscillation and the ultrasonic stress waves in soils of described oscillatory system, ultrasonic self-diffusion and the annihilation of closed boundary occurs.

13. each described method is characterized in that according to claim 1-3, the precipitation of alloy phase comprises the throw out of silicon in aluminium alloy, and the strength of materials that improves is provided, and owing to the control ultrasonic impact is activated.

14. each described method is characterized in that according to claim 1-3, unstable phase comprises the copper in the aluminium alloy, is fixed in soft ultrasonic contact and assault phase, thereby prevents the precipitation in sosoloid and prevent deteriorated expansion.

15. each described method according to claim 1-3, it is characterized in that, since after its soft phase place with the ultrasonic impact stdn, activated the throw out in the sosoloid, comprise " oppositely " self-diffusion of the copper in the aluminium alloy, its cause structural bond reduction, produce the structural stress centrostigma of hiding that is caused by external force and the metal that causes subsequently is deteriorated, and be accompanied by the recovery of strength and ductility of the forfeiture of alloy.

16. each described method according to claim 1-3, it is characterized in that, described ultrasonic impact stdn is owing to occur after its soft phase place startup in the activation of migration mutually, and described activation is accompanied by the fatigue resistance of the raising that the reduction by the distribution density of potential stress concentration point under the nanostructure level causes.

17. each described method according to claim 1-3, it is characterized in that, as the means that improve anti-deterioration, the activation of the segmentation of microscopic level material structure, homogenizing and arrangement under ultrasonic impact since described task determine like that, the standard parameter of the soft phase place of described ultrasonic impact and power phase place is subsequently occured.

18. each described method according to claim 1-3, it is characterized in that, nano level final optimization pass mode as the surfacing structure, decrystallized activation since by described task determine like that, control soft phase place and process that the dynamicmodel of ultrasonic impact standard parameter is caused and occuring.

19. each described method according to claim 1-3, it is characterized in that, by controlling the soft power phase place of described ultrasonic impact, preventing the deteriorated forming core of described material under initial conditions, and prevent and during its life-time service or afterwards deteriorated of the structure that suppresses described material.

20. each described method is characterized in that according to claim 1-3, the protection aluminium alloy to be preventing corrosion spalling, and/or recovers and/or repair because peeling off the character of impaired aluminium alloy.

21. each described method is characterized in that according to claim 1-3, obtains at least a technique effect, comprising:

By the soft ultrasonic impact of superpower (PSUI) and with adaptation on-off time of the synchronous driving pulse of the soft ultrasonic impact of described superpower than regulating (O/OTRM); produce the character that compensation is protected barrier layer and recovered damaged material; wherein in order to implement this control of driving pulse on-off time ratio; pulse width and amplitude adjusted have been used; it starts when needs improve the frequency of synchronizing ultrasound impact; it has time-out not enough between predetermined oscillation independently suppressed or for the independent length of recovering the transient process of deficiency of vibration, thus realization:

During each ultrasonic impact, the control of the plastic deformation intensity distribution on time and space;

The control of the surface parameter under middle structure and crystalline texture rank, the strain deformation state of described material, and the penetration depth in existing or possible failure area; And/or

The stabilization of phase, under the external conditions of heating, load and/or environment, the structure of described material in its unstable region and the homogeneity of character.

22. each described method is characterized in that according to claim 1-3, realizes at least a technique effect, comprising:

The inclusion contact structures fragment that anti-absorption is protected and prevented from adsorbing;

Improve transport property and the combination loss of dross inclusion adsorption and surfactant and adsorption surface, described material or described material structure affected area; And/or

Optimize unrelieved stress in the layer on the middle structure on described processed surface, described surface and roughness, described surface and the anti-adsorptivity of surfacing by the raising of density of material in the layer on described surface.

23. each described method is characterized in that according to claim 1-3, realizes at least a technique effect, comprising:

The heat resistanceheat resistant and the heat resistanceheat resistant-physical disturbance that under initial conditions and in use improve;

Based on the generation of the compensation barrier layer of distributed unrelieved stress, stress relaxation in heat history and heat-physical disturbance zone and deformation gradient, in the textural defect zone, fill in intergranular space and the ultrasonic diffusion at grain boundaries at least one with grain material, keep and restorer character; And/or

As the time in the reduction braking and the means of thermosteresis, optimize frictional connection spare surface.

24. each described method is characterized in that according to claim 1-3, realizes at least a technique effect, comprising:

To the protection of affected original surface and the recovery of material character;

The compensation barrier layer of residual compressive stress in sight and crystalline texture, decrystallized surfacing, the described surfacing of establishment in the correction is set based on the amplitude variations with " transverter-pressure head-surface " system in the soft ultrasonic impact process of high energy;

In the structural failure zone that intergranular corrosion causes in pulse and the ultrasonic diffusion of grain boundaries; And/or

The plastic deformation of described material, the inhomogeneity raising of crystallite size, fill the intergranular space or in the impulse ultrasound diffusion of grain boundaries with grain material.

25. each described method is characterized in that according to claim 1-3, realizes at least a technique effect, comprising:

Produce galvanic corrosion compensation barrier layer under the initial conditions of described material and in the recovery of at least a character;

Strengthen the homogeneity of the crystalline texture on the microcosmic on described surface and how much of macroscopic views, the described surface of described material, as the nanocrystal on the described surface of the described material of the retardance means of anodic process and decrystallized;

The establishment in surface plasticity deformation, stress district and the density of material of raising are with the localization of the galvanic corrosion of obstruction surface imperfection; And/or

Structure in the surface appearance that the formation of the soft ultrasonic impact mechanism of use superpower strengthens and the surface.

26. each described method is characterized in that according to claim 1-3, realizes at least a technique effect, comprising:

Repair at needs in the situation of described material character; on layer of scale; by using the soft ultrasonic impact mechanism of superpower; produce chemical corrosion compensation barrier layer under the initial conditions of described material and in the recovery of described at least a character, thus strengthen quality in the applying of protective refractory coating and in the repetition in these operations and improve the surface alloying degree of depth and.

27. each described method is characterized in that according to claim 1-3, realizes at least a technique effect, comprising:

Use the soft ultrasonic impact mechanism of superpower to produce radiation corrosion compensation protection barrier layer under the initial conditions of affected described material and in the recovery of at least a character, thereby:

In the middle enhancing quality of applying of protective refractory and radiation resistant coating and the raising surface alloying degree of depth;

Enhancing is in roughness, middle structure, the microcrystallite structure and material surface appearance aspect decrystallized; With

Produce favourable stress field and improve surfacing density, wherein, these operate in repetition on the damaged layer provides the radioresistance of surfacing in affected original material aspect recovery.

28. each described method is characterized in that according to claim 1-3, realizes at least a technique effect, comprising:

Use the soft ultrasonic impact of superpower (PSUI) mechanism producing the compensation protective barrier layer that prevents that etching crack from forming under the initial conditions of described material and in the recovery in described its at least a character, thereby:

Strengthen quality, the binding property that is applied to possible or actual impaired lip-deep protective coating or improve its alloying degree of depth, so that under middle constructional aspect that strengthen or appointment, in the enhancing of material surface or modification, in material surface, bring out favourable stress to predetermined depth;

Change described material structure and create the stress-deformation state of described material structure, so that can not can reduce absorbent solution negatively charged ion on the strong textural defect of surface energy and reduction atom at dislocation movably and other;

The crack nucleation that strengthens structure in the surface and prevent from being caused by the wedge of surfactant when it is adsorbed in the described lip-deep microfissure of described material;

Described processed surface in the middle structure with enhancing produces the stress field, its magnitude and the degree of depth are enough to prevent the high crack growth rate that caused by the anode dissolution that metal accelerates in the crackle substrate, and wherein stress-deformation state is usually concentrated by tensile stress and determined.

29. each described method is characterized in that according to claim 1-3, realizes at least a technique effect, comprising:

Use the soft ultrasonic impact of superpower (PSUI) mechanism, thereby:

Strengthen surface alloying quality, bond strength and electrolytic coating density; And/or

Described processed surface in the middle structure with enhancing produces the stress field, its magnitude and the degree of depth are enough to prevent to be reduced by the strength property that following at least one reason causes and brittle crack forms: the infiltration of atomic hydrogen in space and other lattice imperfection, hydrogen changes into the molecular gas that produces pressure between high segment, and/or atomic hydrogen and metal and impurity forms chemical compound and is adsorbed on parts and the subsurface defect surface, this reduce metallic surface can and anti-brittle rupture.

30. method according to claim 29 produces the stress field on the described processed surface of the middle structure with enhancing, its magnitude and the degree of depth are enough to prevent to be reduced by the strength property that the infiltration reason of atomic hydrogen in hole causes and brittle crack forms.

31. each described method is characterized in that according to claim 1-3, realizes at least a technique effect, comprising:

Use the soft ultrasonic impact of superpower to produce middle structure and the stress field that strengthens on described surface, its magnitude and the degree of depth are enough to prevent the formation of strength property reduction, brittle crack, the reduction that the pre-failed areas of solid metal, surface energy and anti-metal fracture are infiltrated in molten metal absorption.

32. each described method is characterized in that according to claim 1-3, realizes at least a technique effect, comprising:

Use the soft ultrasonic impact of superpower to produce density, roughness, middle structure and the stress field of described lip-deep enhancing, its magnitude is enough to prevent with the degree of depth because the contacting or make solids break away from described material structure owing to solids clash on described affected surface of material and fluxion, gaseous environment or its particle of carrying secretly.

33. each described method is characterized in that according to claim 1-3, realizes at least a technique effect, comprising:

Use the soft ultrasonic impact of superpower to produce that the density that strengthens, middle constructional aspect and crystal grain are filled size and in surface and subsurface compression macrostress and microstress field, its magnitude and the degree of depth be enough to prevent in crystal boundary and substructure, to form the rotation of the rotation of bending, stratification, crystal grain of microvoid and movement, twinnig, slip plane and relative movement, mosaic block and relatively move, polygonization, diffusion plasticity, recrystallize and/or the defect on microcosmic and macroscopic aspect and structure deteriorate.

34. method according to claim 33, size filled by density, middle constructional aspect and the crystal grain that wherein uses the soft ultrasonic impact generation of superpower to strengthen and in surface and subsurface compression macrostress and microstress field, its magnitude and the degree of depth are enough to prevent form tiny crack or slip in crystal boundary and substructure.

35. each described method is characterized in that according to claim 1-3, realizes at least a technique effect, comprising:

Use the soft ultrasonic impact of superpower to produce the density of material that strengthens, the middle structure on the described material surface, with make described lip-deep plastic deformation and the stdn of stress field, its magnitude and the degree of depth are enough to prevent by the deteriorated strength of materials reduction of performance that causes of microstructure, this microstructure is deteriorated to comprise following at least one: little surface of expanding in deformable body absorbs molecule from environment, and/or significantly do not changing in the situation of microstructure, with the metallographic phase condition that the is converted into cost disadvantageous stabilization in time of unstable phase.

36. each described method is characterized in that according to claim 1-3, realizes at least a technique effect, comprising:

Use the soft ultrasonic impact of superpower, by the upper and lower plastic deformation in described surface and the stdn of stress field, obtain density and the middle structure of the enhancing of described processed material, its magnitude and the degree of depth are enough to prevent the formation that is increased sharply of the yield strength of brittle crack, it is caused by the knocking out under neutron current or displacement cascade in the metal lattice and depends on the energy of neutron transfer in the atoms metal, and prevents from subsequently being had along the edge formation of the high vacancy hole concentration that the zone of the calking interstitial atom density of raising centers on.

37. each described method is characterized in that according to claim 1-3, realizes at least a technique effect, comprising:

Use the soft ultrasonic impact of superpower, the density that its level and time parameter meet the enhancing through testing the processed material of definite acquisition with and the requirement of guaranteed middle structural integrity, with to partial points heating and the heat dissipation speed that dissipates from this plastic deformation zone, plastic deformation itself and the formation of the stress field about described processed surface and the requirement of normalization condition, magnitude and the degree of depth of stress field are enough to:

-in special these failure areas that caused by the synergistic effect of corrosion and hydrogen embrittlement, prevent the formation of metallic surface corrosion spalling, focal point of stress and the loss of intensity or recovery,

-preventing from causing the formation of the unstable phase of described precipitation of material, it produces the strong content of the structure that reduces and the strength of materials, and prevents intergranular corrosion,

-when its border of sealing and activation self-diffusion process, eliminate structure both macro and micro defective, optional hole or other intergranular of comprising is interrupted,

The corrosion cracking of the self-diffusion at-activation structure segment boundaries place and elimination grain boundaries,

-recovery of sedimentary counter diffusion and stable phase is provided,

-raising of the intensity of the precipitation, concentration and density of alloying element and described processed material is provided,

-guarantee compensation, the redistribution or lax of construction machine stress in the concentrated area of being caused by the throw out from the sosoloid of unstable phase,

-form superfine crystal particle structure, decrystallized, the intensity of described material and the raising of erosion resistance thereof.

38. each described method is characterized in that according to claim 1-3, realizes at least a result, comprising:

In cast iron brake drum and dish, structure is to prevent by using and process the destruction that causes in the introducing of high-level stress, the raising of the microhardness of upper layer and/or the protection.

39. each described method is characterized in that according to claim 1-3, realizes at least a result, comprising:

Under strong stdn plastic deformation, change the inhibition of the surface imperfection of structure deteriorate in the generation in surface layer structure, stress zone and/or the in use initiation, thereby improve the corrosion strength in the cast iron pipe.

40. each described method is characterized in that according to claim 1-3, realizes at least a result, comprising:

The introducing, stress concentration of high level stress reduces, ultrasonic plastic deformation and described processed material be in the structural modification of area of stress concentration; wherein; sonic oscillation condition, pressure and pressure head size guarantee to use structure in the soft ultrasonic impact protection of superpower using and processing between the standby period of surface is induced and destroyed and operation destroys preventing, thereby improve the fatigue resistance of welding iron.

41. each described method is characterized in that according to claim 1-3, realizes at least a result, comprising:

In described processed surface and processed material, introduce high-level stress and structural modification thereof; wherein, sonic oscillation condition, pressure and pressure head size guarantee to use described ultrasonic impact use and surface treatment process in the protection structure to strengthen the corrosion fatigue strength of steel.

42. each described method is characterized in that according to claim 1-3, realizes at least a result, comprising:

Block structure is in the arrangement of nanometer aspect and the establishment in stress zone, this stress zone is enough to structure deteriorate in the such standardized ultrasonic impact that is determined by task and the quasistatic that is caused by operating physical force subsequently and Dynamic Loading hinder during processed material, thus the shock strength of enhancing steel.

43. each described method is characterized in that according to claim 1-3, realizes at least a result, comprising:

The middle structure deteriorate of steel is arranged and/or suppressed to the strong ultrasonic plastic deformation of processed material, the nano level of microstructure.

44. each described method is characterized in that according to claim 1-3, realizes at least a result, comprising:

Strong ultrasonic plastic deformation under the stdn ultrasonic impact of surfacing under high deformation loading rate, the local heating in the phase change region and/or from the rapid heat extraction of shock zone, thus white layer in the steel obtained.

45. each described method is characterized in that according to claim 1-3, realizes at least a result, comprising:

Strengthen diffusion process and metal recrystallize under the effect of ultrasonic wave, sound stream, acoustic pressure and cavitation, this effect is by pressure head sonic oscillation initiation synchronous with the carrier oscillation of sonic oscillation system in the ultrasonic impact process, thus the metallic crystal of enhancing steel.

46. each described method is characterized in that according to claim 1-3, realizes at least a result, comprising:

The activation of the strong ultrasonic plastic deformation of surfacing and/or the diffusion process that in the ultrasonic impact process, is caused by ultrasonic wave, thereby the mechanical properties of enhancing steel.

47. each described method is characterized in that according to claim 1-3, realizes at least a result, comprising:

The introducing, stress concentration of high level stress reduce and/or create prevent from directed plastic deformation zone, forming in the physical barrier layer of textural defect and the stress corresponding with defect level, thereby strengthen the safe range of stress of aluminium alloy.

48. each described method is characterized in that according to claim 1-3, realizes at least a result, comprising:

The introducing, stress concentration of high level stress reduce, and/or suppress possible middle structure deteriorate by ultrasonic recrystallize in sosoloid and the ultrasonic diffusion that activates grain boundaries in described ultrasonic impact process, thereby strengthen the high-cycle fatigue strength of aluminium alloy.

49. each described method is characterized in that according to claim 1-3, realizes at least a result, comprising:

The strong plastic deformation of the processed nearly upper layer of material, the ultrasonic diffusion on the defective border that in described material, is space or form of discontinuity of under ultrasonic impact, sealing, and/or at the stdn ultrasonic impact be accompanied by under its effect that impact of structure is produced and inhibition to stress corresponding to the middle textural defect in the stdn plastic deformation zone and plastic deformation degree, wherein, described impact causes at the anti-deformation behavior that reduces in the process because of spreading in the described material of described ultrasonic impact deformation by ultrasonic stress waves in soils especially, thereby suppresses the hole of aluminium alloy until predetermined depth and prolong the aluminium alloy life-span.

50. each described method is characterized in that according to claim 1-3, realizes at least a result, comprising:

Because ultrasonic plastic deformation, because delay dislocation and other textural defect in the plastic deformation structure keeps or the raising metal, comprises the shock strength in steel and the aluminium alloy, wherein said shock strength may reduce under traditional plastic deformation, causes the reserves of the reduction of material plasticity.

51. each described method is characterized in that according to claim 1-3, realizes at least a result, comprising:

Owing to the structural changes that the predetermined control by the ultrasonic impact parameter causes, enhanced surface layers during ultrasonic impact mechanical workout;

The conversion of the two-phase condition of original texture in the upper layer, and the formation of more solid-state eutectic structure; And/or

Alloy inclusions is moved on the described processed surface, strengthens thus described affected surface.

52. 1 method realizes that wherein at least a result comprises the structural changes that causes owing to the predetermined control by the ultrasonic impact parameter according to claim 5, strengthens the upper layer of steel during ultrasonic impact mechanical workout.

53. 1 method realizes that wherein at least a result comprises the conversion of the two-phase condition of original texture in the aluminium alloy according to claim 5, and the formation of more solid-state eutectic structure.

54. 1 method according to claim 5 realizes that wherein at least a result comprises that alloy inclusions moves on the surface of the silicon inclusion in the aluminium alloy, strengthens described affected surface thus.

55. each described method is characterized in that according to claim 1-3, realizes at least following result:

The ultrasonic impact of grain boundaries spreads, thereby recovers the performance of aluminium alloy behind corrosion spalling.

56. each described method is characterized in that according to claim 1-3, realizes at least a result, comprising:

Grain refining is provided, and the raising of intensity, because this is because additional deformation forms higher dislocation desity and twin structure, formation microstrip structure, microstrip structure is subdivided into sub-micron grain, and/or subgrain is further broken into pieces so that the crystal grain isometry.

57. 6 method wherein provides grain refining in aluminium alloy according to claim 5, and the raising of intensity.

58. each described method is characterized in that according to claim 1-3, realizes at least a result, comprising:

Because with ultrasonic impact, local heating, heat abstraction, the stdn of ultrasonic stress waves in soils distribution occasion with because the stdn of Plastic Deformation deformation, the geometric dynamic recrystallization of nano level and micron order crystal grain is provided, wherein striking energy and local Heating temperature reach for the favourable constructional aspect of described material and are critical degree, and causing throw out migration favourable in little band occurs, it is accompanied by the raising of metal strength and the shoddy voltinism of resistance.

59. 8 method according to claim 5, wherein striking energy and local Heating temperature reach the degree that causes throw out migration favourable in aluminium alloy.

60. each described method is characterized in that according to claim 1-3, realizes at least a result, comprising:

The introducing, surface layer structure modification of high level stress, in the ultrasonic diffusion of closing of the frontier place of the optional textural defect that comprises hole, prevent from destroying and suppressing the middle structure deteriorate of microscopic level and macro-level, thereby strengthen the corrosion fatigue strength in the bronze.

61. each described method according to claim 1-3, it is characterized in that, under the condition that middle structural integrity is recovered, the control break of the soft power phase place of ultrasonic impact corrosion sample, comprise the work crack nucleation mechanism in the aluminium alloy, wherein, the crack nucleation in the intergranular corrosion destroyed area and expansion prevent by sealing and eliminating its border subsequently, it carries out under strong plastic deformation and ultrasonic diffusion subsequently, and the corrosion-resistant and antifatigue that improves thus material is destructive.

62. each described method is characterized in that according to claim 1-3,

The control of at least one the ultrasonic impact parameter in sum velocity, striking energy, repetition rate, attack time and/or impact amplitude and the phase place when impacting beginning is determined by the specific tasks based on tentation data, wherein, described at least one parameter is being set to the dispersity of random value from 5% based on predetermined technique requirement and the predetermined predetermined terminal result who occurs.

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