CN105784238B - A kind of measuring method and its system of material surface residual stress - Google Patents
A kind of measuring method and its system of material surface residual stress Download PDFInfo
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- CN105784238B CN105784238B CN201610333203.1A CN201610333203A CN105784238B CN 105784238 B CN105784238 B CN 105784238B CN 201610333203 A CN201610333203 A CN 201610333203A CN 105784238 B CN105784238 B CN 105784238B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
- G01L5/0047—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes measuring forces due to residual stresses
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Abstract
The invention discloses a kind of measuring methods and its system of material surface residual stress.The present invention is in contact, and be continuously pressed into sample to be tested using the region to be measured of press-in needle point and sample to be tested；Deformeter measures the variation of loaded load F by the strain signal that foil gauge exports, impedance analyzer measures the electromechanical impedance frequency response of piezoelectric patches on each piezoelectric beam, the projected area S of the contact area of press-in needle point and sample to be tested can be obtained by electromechanical impedance frequency response, by being continuously pressed into the F S curves that can be obtained in process of press in, and then obtain residual stress；Convenient test of the present invention is quick, and efficiency is higher；Without knowing the properties such as plasticity, the yield stress of material in advance；It is a kind of test method in place, the in-site measurement suitable for on-position measure and engineering, and the test system of automation can be extended further to；This method only needs strain measurement module and impedance chip module, therefore is measured suitable for large-scale.
Description
Technical field
The invention belongs to detect metering field, and in particular to a kind of measuring method of material surface residual stress and its be
System.
Background technology
Residual stress generally arises from the processes such as mechanical processing, non-homogeneous heated and chemical attack, is widely present nuclear power
Material, the undercarriage for bearing repeated stock effect, space shuttle the significant points such as function of surface coating.Residual stress pair
Fracture toughness, fatigue strength and the service life of material have significant impact, and accurately the residual stress of material is characterized,
There is extremely important meaning to the performance and used life of measurement structure damage, accurate evaluation structure.
The residual stress origin cause of formation is extremely complex, and theoretical model difficult to use is predicted, in practice mostly using laboratory facilities into
Row measures.Current main residual stress measuring method can be divided into physical method and mechanical means：Physical method mainly passes through survey
It measures influence of the residual stress to physical characteristics of materials and carrys out measurement remnant stress value, common method includes X-ray diffraction method and surpasses
Sonic method etc.；Mechanical means mainly by material carry out mechanical treatment, by contrast material before treatment after strain or position
It moves variation and carrys out measurement remnant stress value, common method includes boring method and Crack Compliance Method etc..Physical method is a kind of to material
Expect lossless method, but equipment is mostly costly, and institute's depth measurement degree is extremely shallow used by physical method；Mechanical means needs brokenly more
Bad material is a kind of test method damaged, and film coating cannot be measured.
Instrumentation plunging is a kind of high-precision mechanical property characterizing method in place, and surface residual stress is to process of press in
In tip-sample projected area, the elasticity that occurs after point, unloading of loaded load, press-in work(/ initial plastic deformation restores and pressure
There is influence, therefore residual stress can be characterized by being pressed into test in the curvature for entering curve.Traditional press-in test
Method is based on nano-hardness tester, more demanding to test environment and testing cost, and a large amount of data is needed to carry out empirical equation
Fitting, therefore the measurement under not being suitable for actual conditions.
Invention content
For more than the deficiencies in the prior art, the present invention proposes a kind of completely new material surface residual stress
Measuring method, this method give residual stress size and the F-S curves of process of press in, wherein F is loaded load, and S is press-in
The projected area of the contact area of needle point and sample to be tested, on this basis, the present invention are proposed based on the residual of dynamo-electric impedance method
Residue stress detector, the F-S curves that are obtained by being continuously pressed into sample to be tested characterize residual stress.Proposed by the invention
Method can accurately measure residual stress, be that one kind has larger potentiality without a large amount of data fitting empirical formula
Residual stress measuring method in place.
An object of the present invention is to provide a kind of measuring systems of material surface residual stress.
The measuring system of the material surface residual stress of the present invention includes：Residual stress detector, impedance analyzer, strain
Instrument and computer control system；Wherein, residual stress detector include support ring, height adjustable seats, piezoelectric beam, piezoelectric patches,
It is pressed into needle point and foil gauge；The bottom of support ring sets multiple height adjustable seats in central distribution, to adjust support ring
Highly；Support ring is internally provided with the piezoelectric beam of multiple distributions that are centrosymmetric, and one end of each piezoelectric beam is fixed on support
On ring, the other end intersects at the center of support ring with other piezoelectric beams；In the upper and lower surface of each piezoelectric beam, pressure is set respectively
Electric piece；Press-in needle point is set in the lower surface at the center that multiple piezoelectric beams intersect；Upper table at the center that multiple piezoelectric beams intersect
Face sets foil gauge；Piezoelectric patches is connected to impedance analyzer；Foil gauge is connected to deformeter；Impedance analyzer and deformeter difference
Computer control system is connected to by data line.
During test, support ring is fixed on to the surface of sample to be tested by height adjustable seats, it is adjustable by adjusting height
Bearing adjusts the height of support ring so that the region to be measured of press-in needle point and sample to be tested is in contact, and be continuously pressed into be measured
Sample；The strain signal monitoring that deformeter is exported by foil gauge is pressed into the contact force of needle point i.e. the variation of loaded load F,
Impedance analyzer measures the electromechanical impedance frequency response of piezoelectric patches on each piezoelectric beam, and press-in needle can be obtained by electromechanical impedance frequency response
The projected area S of point and the contact area of sample to be tested, residual stress detector process of press in can be obtained by being continuously pressed into
In F-S curves, pass through F-S curves obtain residual stress.
Computer control system includes：Impedance measurement module, for controlling impedance analyzer to residual stress detector
Electromechanical frequency response measures；Strain measurement module, for measuring and analyzing the strain signal of deformeter output；Calculate analysis mould
Block obtains computational representation residual stress after the F-S curves of process of press in.
It is another object of the present invention to provide a kind of measuring methods of material surface residual stress.
The residual stress σ of material surfaceRIt is divided into grade twin shafts residual stress and non-grade twin shafts residual stress, waits twin shafts remnants should
Power is represented by σR=σx=σy, σxFor the residual stress size in x directions, σyResidual stress size for y directions；It is non-to wait twin shafts residual
In residue stress, σx≠σy, and have σx=k σy, k is the ratio of principal stress, and k ≠ 1 is previously known.
The measuring method for waiting twin shafts residual stress of the material surface of the present invention, includes the following steps：
1) measuring system of material surface residual stress is completed；
2) the F-S curves of the process of press under without residual stress state are obtained by without residual stress sample, so as to obtain
Fitting parameter C01And C02；
3) residual stress detector is fixed on to the surface of sample to be tested by multiple height adjustable seats；
4) by adjusting the height of height adjustable seats adjustment support ring so that the area to be measured of press-in needle point and sample to be tested
Domain is in contact and is pressed into sample to be tested point by point；
5) deformeter measures loaded load F by the strain signal that foil gauge exports, while is measured using impedance analyzer
The electromechanical impedance frequency response of piezoelectric patches on each piezoelectric beam obtains contact of the press-in needle point with sample to be tested by electromechanical impedance frequency response
The projected area S in region records the loaded load F of every bit and projected area S respectively；
6) step 4)~5 are repeated), sample to be tested is continuously pressed into, obtains the F-S data of the process of press in of sample to be tested, from
And obtain the F-S curves of the process of press in of sample to be tested；
7) by the F-S curves of the process of press under the F-S curves of the process of press in of sample to be tested and without residual stress state
It is compared, it is residual tension or residual compressive stress to judge residual stress；
8) according to step 7) judgement as a result, based on least square method, with reference to obtained fitting parameter C01And C02, adopt
With residual tension or residual compressive stress formula, residual stress is obtained.
Wherein, in step 2), the F-S curves for obtaining the process of press under without residual stress state obtain fitting parameter C01
And C02Include the following steps：
A) residual stress detector is fixed on to the surface of without residual stress sample by multiple height adjustable seats；
B) by adjusting the height of height adjustable seats adjustment support ring so that press-in needle point is sent out with without residual stress sample
It is raw to contact and be pressed into without residual stress sample point by point；
C) deformeter measures the loading of the process of press under without residual stress state by the strain signal that foil gauge exports
Load, while using the electromechanical impedance frequency response of piezoelectric patches on each piezoelectric beam of impedance analyzer measurement, pass through electromechanical impedance frequency response
The projected area of press-in needle point and without residual stress sample is obtained, records the press-in under the without residual stress state of every bit respectively
The loaded load F of process and projected area S；
D) step b)~c is repeated), the F-S data that without residual stress state is pushed down into process are obtained, so as to obtain no remnants
Stress state is pushed down into the F-S curves of process；
E) based on least square method, according to formula F=C01S2+C02S is pushed down into without residual stress state the F-S of process
Data are fitted, and obtain fitting parameter C01And C02。
In step 7), residual tension can increase contact area, and residual compressive stress can reduce contact area.If treat test sample
The F-S curves of the process of press in of product decline compared with the F-S curves of the process of press under without residual stress state, the meaning of decline
To there is the loaded load of residual stress lower in the case of identical S values, then residual stress is residual tension；If sample to be tested
The F-S curves of process of press in rise compared with the F-S curves of the process of press under without residual stress state, and the meaning of rising is phase
With the loaded load higher for having residual stress in the case of S values, then residual stress is residual compressive stress.
In step 8), the formula of residual tension isThe formula of residual compressive stress
ForWherein, FSTo have the loaded load under residual stress state, SSTo there is remaining answer
The projected area of the contact area of press-in needle point and sample to be tested under power state, a are the complementary angle for the semi-cone angle for being pressed into needle point.
The non-measuring method for waiting twin shafts residual stress of the material surface of the present invention, includes the following steps：
1) measuring system of material surface residual stress is completed；
2) being decomposed into the twin shafts residual stress such as non-waits biaxial stresses part and pure shear stress part to measure, wherein pure
The press-in for being pressed into needle point, which is not present, in shear stress part influences, and the stress value size for waiting biaxial stresses part is
3) the F-S curves of the process of press under without residual stress state are obtained by without residual stress sample, so as to obtain
Fitting parameter C01And C02；
4) residual stress detector is fixed on to the surface of sample to be tested by multiple height adjustable seats；
5) by adjusting the height of height adjustable seats adjustment support ring so that the area to be measured of press-in needle point and sample to be tested
Domain is in contact and is pressed into sample to be tested point by point；
6) loaded load F is measured, while measure piezoelectric patches on each piezoelectric beam using impedance analyzer using strain signal
Electromechanical impedance frequency response, by electromechanical impedance frequency response obtain press-in needle point and sample to be tested contact area projected area S, point
It Ji Lu not the loaded load F of every bit and projected area S；
7) step 5)~6 are repeated), the F-S data of the process of press in of sample to be tested are obtained, so as to obtain the pressure of sample to be tested
Enter the F-S curves of process；
8) by the F-S curves of the process of press under the F-S curves of the process of press in of sample to be tested and without residual stress state
It is compared, it is residual tension or residual compressive stress to judge residual stress；
9) according to step 9) judgement as a result, based on least square method, with reference to obtained fitting parameter C01And C02, adopt
It is fitted with residual tension or residual compressive stress formula, the stress value for waiting biaxial stresses part for obtaining residual stress is big
It is small
10) according to the ratio k of previously known principal stress, the residual stress size σ in x directions and y directions is respectively obtainedx
And σy.Wherein, in step 9), the formula of the medium biaxial stress part of residual tension is
The formula of the medium biaxial stress part of residual compressive stress isWherein, FSIt is residual to have
Loaded load under residue stress state, SSTo there is the throwing of the contact area of press-in needle point and sample to be tested under residual stress state
Shadow area, a are the complementary angle for the semi-cone angle for being pressed into needle point.
Advantages of the present invention：
The present invention is fixed on the surface of sample to be tested using support ring, by adjusting height adjustable seats adjustment support ring
Highly so that the region to be measured of press-in needle point and sample to be tested is in contact, and be continuously pressed into sample to be tested；Deformeter is by answering
The strain signal for becoming piece output measures the variation of loaded load F, and impedance analyzer measures the electromechanics of piezoelectric patches on each piezoelectric beam
Impedance frequency response can obtain the projected area S of the contact area of press-in needle point and sample to be tested by electromechanical impedance frequency response, pass through
Continuous press-in can obtain the F-S curves in residual stress detector process of press in, and then obtain residual stress.The present invention uses
The residual stress detector of special designing is continuously pressed into sample to be tested, by tracking F-S curve of the residual stress to process of press in
Influence characterize residual stress.It is compared with other residual stress test methods, present method be advantageous in that：Convenient test is fast
Victory, this method is without a large amount of experimental fit empirical equation or is iterated, it is only necessary to by measuring F-S curves, therefore
Efficiency is higher；Without knowing the properties such as plasticity, the yield stress of material in advance；This method is a kind of test method in place, remaining
Stress detection device, which can be improved, is made portable equipment, therefore the in-site measurement suitable for on-position measure and engineering, and can be with
Extend further to the test system of automation；Compared with the press-in instrument of the precision such as nano impress, this method only needs to strain
Measurement module and impedance chip module, therefore measured suitable for large-scale.
Description of the drawings
Fig. 1 is the schematic diagram of the measuring system of the material surface residual stress of the present invention；
Fig. 2 is the schematic diagram of the residual stress detector of the measuring system of the material surface residual stress of the present invention, wherein,
(a) it is stereogram, (b) is bottom view；
Fig. 3 is the schematic diagram of influence of the surface residual stress to the loaded load of press-in needle point, wherein, (a) is drawn to be remaining
The schematic diagram of stress, (b) are the schematic diagram of residual compressive stress；
Fig. 4 is the F-S curve graphs of the process of press under the without residual stress state of one embodiment of the present of invention；
Fig. 5 be one embodiment of the present of invention material surface residual stress to be pressed into needle point process of press in F-S
The schematic diagram of the influence of curve, wherein, (a) is the schematic diagram under residual tension state, and (b) is under residual compressive stress state
Schematic diagram.
Specific embodiment
Below in conjunction with the accompanying drawings, by specific embodiment, the present invention is further explained.
As shown in Figure 1, the measuring system of the material surface residual stress of the present embodiment includes：Residual stress detector 1, resistance
Analysis resistant instrument 2, deformeter 3 and computer control system 4；Wherein, as shown in Fig. 2, residual stress detector include support ring 11,
Height adjustable seats 16, piezoelectric beam 12, piezoelectric patches 13, press-in needle point 14 and foil gauge 15；The bottom of support ring 11 sets 3
The height adjustable seats 16 of central distribution adjust the height of support ring；Support ring 11 is internally provided with 3 distributions that are centrosymmetric
Piezoelectric beam 12, one end of each piezoelectric beam 12 is fixed in support ring 11, and the other end intersects at support with other piezoelectric beams
The center of ring；Piezoelectric patches 13 is respectively arranged in the upper and lower surface of each piezoelectric beam 12；At the center that 3 piezoelectric beams intersect
Lower surface setting press-in needle point 14, the region to be measured 5 for being pressed into needle point and sample to be tested is in contact；Intersect in 3 piezoelectric beams
The upper surface setting foil gauge 15 at center；Piezoelectric patches 13 is connected to impedance analyzer 2；Foil gauge 15 is connected to deformeter 3；Impedance
Analyzer 2 and deformeter 3 are connected to computer control system 4 by data line respectively.
In the present embodiment, press-in needle point 14 is using Vickers indenter made of diamond；Piezoelectric beam 12 is steel elongate strip.
The curve of F-S of the present invention by the press-in needle point of measurement remnant stress detection device during sample to be tested is pressed into
Change the residual stress to characterize sample to be tested, next the method for the present invention is specifically described.
1. the measurement of projected area：
The present invention is tracked, and then by the projected area to press-in needle point and the contact area of sample to be tested to remnants
Stress is characterized, and illustrates measuring method of the present invention to the projected area of contact area first here.Needle point is pressed into when measuring
When being contacted with sample to be tested, press-in needle point-sample to be tested contact system is formed, can be measured by impedance analyzer centrosymmetric
The resonant angular frequency of residual stress detector is ω0, it is double which can be equivalent to a piezoelectricity
Chip beam, according to the dynamo-electric impedance method principle of piezo-electricity double-chip-beam it is found that the contact stiffness k of press-in needle point and sample to be testedtIt can
It is expressed as：
Wherein, mtTo be pressed into the quality of needle point,For residual stress detector equivalent stiffness and can be by demarcating
It arrives, λb0For wavelength and For residual stress detector equivalent density and can by calibration obtain, L is
The length of piezoelectric beam in residual stress detector.After contact stiffness is obtained, press-in needle point can be calculated to obtain according to contact theory
Projected area S with the contact area of sample to be tested is：
Wherein, EreTo be pressed into the decrement Young's modulus of needle point-sample to be tested contact system, and the value is given value.
It only needs to be tracked resonant angular frequency using impedance analyzer during measurement, you can be calculated using formula (2)
The projected area S of the contact area of needle point and sample to be tested is pressed into, which is press-in needle point and the direct active region of sample to be tested
The projected area in domain.
2. influence of the grade twin shafts residual stress to needle point loaded load
Influence of the twin shafts residual stress such as analysis to press-in needle point process of press in first, waits twin shafts residual stress to be represented by
σR=σx=σy, σRFor residual-stress value, σxFor the stress intensity in x directions, σyFor the stress intensity in y directions, the present invention passes through end
Band figurate press-in needle point in portion's is continuously pressed into sample to be tested, and Fig. 3 gives residual stress to adding in needle point process of press in
The influence of load F is carried, wherein Fig. 3 (a) is influence of the residual tension to loaded load, and Fig. 3 (b) is residual compressive stress to loading
The influence of load, a is the complementary angle for the semi-cone angle for being pressed into needle point, a=22 ° for Vickers indenter.
As shown in Fig. 3 (a), since the hydrostatic stress below press-in needle point is on being pressed into the press-in of needle point without influence, the present invention
The twin shafts residual tension σ such as generalRIt is decomposed into a hydrostatic pressure part σH=σRWith the simple stress-σ of pressing directionz=-σH, then
Influence of the residual tension to press-in can be described as increasing size as σ in pressing directionRThe pressure of S, wherein S are press-in needle point
With the projected area of the contact area of sample to be tested, the definition of projected area here is has residual stress effect lower using electromechanical resistance
The area value that anti-method is directly calculated, the value are characterized under residual stress effect, contact of the press-in needle point with sample to be tested
The projected area in region.By analysis chart 3 (b) it is found that residual compressive stress will cause loaded load to reduce σRsinaS。
As can be seen that residual tension can increase projected area, and reduce the nominal hardness of sample to be tested；And remaining draw should
Power can reduce the projected area of sample to be tested, and increase the nominal hardness of sample to be tested.
3. influence of the grade twin shafts residual stress to the F-S curves of process of press in
Fig. 4 gives the F-S curves in a typical press-in needle point process of press in, the physics rule in process of press in
Rule can use series functions to describe the F-S curves in process of press in.Here the present invention is by taking quadratic polynomial as an example, to F-S's
Relationship is described, then has：
F=C01S2+C02S+C03 (3)
Wherein, C01, C02And C03For fitting of a polynomial coefficient, due to before contact start, projected area S be zero when
It waits, contact load F is necessarily zero, then has C03=0.
Fig. 5, which gives residual stress, influences the F-S curves of process of press in schematic diagram, and Fig. 5 (a) is the shadow of residual tension
It rings, Fig. 5 (b) is the influence of residual compressive stress, and wherein solid line is the F-S curves under without residual stress state, CS1And CS2It is residual to have
The fitting coefficient of the F-S curvilinear functions of residue stress state, dotted line are the F-S curves having under residual stress state, S1And S2For horizontal axis
On point, F1And F2For the point on the corresponding longitudinal axis, A, B and C are respectively different stress state points.
Analysis chart 5 (a) is it is found that in uniform pressure F1Under, the projected area of without residual stress sample is S1, there is residual stress
The projected area of sample is S2, a process by B points to C points is considered at this time, and residual stress is by σ during thisRIt is discharged into
Zero, nominal projected area remains S2, it is assumed that stress release process σR(t) it is represented by σR(t)=H (t) σR, H (t) is connects
Continue the smooth function of time and have H (t) |T=0=1,That is, stress release process returning for continuous and derivable
Zero process has according to the conclusion of Fig. 5 (a)：
F2=F1+∫d(σR·S) (4)
In addition, had according to Fig. 5：
Simultaneous above formula has：
σR=(C01-CS1)S2+C02-CS2 (6)
In view of σRThe S for definite value2For arbitrary value, then C is understood01=CS1, can finally obtain：
Wherein, F0For the loaded load under without residual stress state, S0It is the press-in needle point under without residual stress state with treating
The projected area of the contact area of sample, formula (7a) be without residual stress state under F-S curve equations, FSTo there is remnants
Loaded load under stress state, SSTo there is the projection of the contact area of press-in needle point and sample to be tested under residual stress state
Area, formula (7b) formula are the F-S curve equations having under residual stress state.
The analytic process of residual compressive stress is identical with tensile stress, and difference lies in residual compressive stress to lead to what loaded load reduced
Calculation formula is slightly different, is had according to the conclusion that Fig. 5 (b) is obtained：
Tension and compression state is distinguished with numerical value is positive and negative, when to out residual stress σRIt is residual tension more than zero, σRIt is less than zero
Residual compressive stress.For example, 100MPa is residual tension, -100MPa is residual compressive stress.
4. non-wait twin shafts residual stress measuring method
It is given above to wait biaxial stresses test method, biaxial stresses (σ is waited for non-x≠σy), σxFor answering for x directions
Power size, σyFor the stress intensity in y directions, the ratio k of previously known principal stress, σx=k σy, residual stress is decomposed into
Biaxial stress part and pure shear stress part measure, and wherein on press-in needle point, there is no influence for pure shear stress part.Deng double
The decomposable process of axial stress is as shown in (9) formula：
After residual stress is decomposed, you can according to the test method equity biaxial stress part provided before the present invention
Stress value sizeAfterwards, according to the ratio k values of known spindles stress, you can derive σ under virgin state of stressxAnd σy
Value.
The ratio k of principal stress can be such as bent by the deformation characteristic of material, be stretched, by out-plane strength specificity analysis
It obtains, the ratio k of principal stress can also be predicted to obtain by finite element method or Elasticity method.Such as pass through deformation
State is estimated：K=0 of flexural deformation, the k=-0.3 of the stretcher strain of general ferrite material, the k=1 of deposition film etc..But
The amplitude of residual stress is unpredictable, can only be obtained by practical measurement.
It is finally noted that the purpose for publicizing and implementing example is to help to further understand the present invention, but this field
Technical staff be appreciated that：Without departing from the spirit and scope of the invention and the appended claims, it is various to replace and repair
It is all possible for changing.Therefore, the present invention should not be limited to embodiment disclosure of that, and the scope of protection of present invention is to weigh
Subject to the range that sharp claim defines.
Claims (10)
1. a kind of measuring system of material surface residual stress, which is characterized in that the measuring system includes：Residual stress detects
Device, impedance analyzer, deformeter and computer control system；Wherein, the residual stress detector includes support ring, highly may be used
Adjust bearing, piezoelectric beam, piezoelectric patches, press-in needle point and foil gauge；The bottom of the support ring sets multiple height in central distribution
Adjustable seats are spent, to adjust the height of support ring；The support ring is internally provided with the piezoelectric beam of multiple distributions that are centrosymmetric,
One end of each piezoelectric beam is fixed in support ring, and the other end intersects at the center of support ring with other piezoelectric beams；Each
The upper and lower surface of a piezoelectric beam sets piezoelectric patches respectively；Press-in needle point is set in the lower surface at the center that multiple piezoelectric beams intersect；
In the upper surface at the center that multiple piezoelectric beams intersect, foil gauge is set；The piezoelectric patches is connected to impedance analyzer；The strain
Piece is connected to deformeter；The impedance analyzer and deformeter are connected to computer control system by data line respectively.
2. measuring system as described in claim 1, which is characterized in that the computer control system includes：Impedance measurement mould
Block, for impedance analyzer to be controlled to measure the electromechanical frequency response of residual stress detector；Strain measurement module, for measuring
With the strain signal of analysis deformeter output；Computation analysis module, computational representation is remaining after obtaining the F-S curves of process of press in
Stress, wherein F are loaded load, and S is the projected area for the contact area for being pressed into needle point and sample to be tested.
3. a kind of material surface of the measuring system of material surface residual stress as described in claim 1 waits twin shafts remnants should
The measuring method of power waits twin shafts residual stress to be expressed as σR=σx=σy, σRFor residual stress, σxResidual stress for x directions is big
It is small, σyResidual stress size for y directions, which is characterized in that the measuring method includes the following steps：
1) measuring system of material surface residual stress is completed；
2) the F-S curves of the process of press under without residual stress state are obtained by without residual stress sample, so as to be fitted
Parameter C01And C02；
3) residual stress detector is fixed on to the surface of sample to be tested by multiple height adjustable seats；
4) by adjusting the height of height adjustable seats adjustment support ring so that send out in the region to be measured of press-in needle point and sample to be tested
It is raw to contact and be pressed into sample to be tested point by point；
5) deformeter measures loaded load F by the strain signal that foil gauge exports, while each using impedance analyzer measurement
The electromechanical impedance frequency response of piezoelectric patches on piezoelectric beam obtains the contact area of press-in needle point and sample to be tested by electromechanical impedance frequency response
Projected area S, respectively record the loaded load F of every bit and projected area S；
6) step 4)~5 are repeated), sample to be tested is continuously pressed into, obtains the F-S data of the process of press in of sample to be tested, so as to
To the F-S curves of the process of press in of sample to be tested；
7) the F-S curves of the process of press under the F-S curves of the process of press in of sample to be tested and without residual stress state are carried out
It compares, it is residual tension or residual compressive stress to judge residual stress；
8) according to step 7) judgement as a result, based on least square method, with reference to obtained fitting parameter C01And C02, using remnants
Tensile stress or residual compressive stress formula, obtain residual stress.
4. measuring method as claimed in claim 3, which is characterized in that in step 2), obtain under without residual stress state
The F-S curves of process of press in obtain fitting parameter C01And C02Include the following steps：
A) residual stress detector is fixed on to the surface of without residual stress sample by multiple height adjustable seats；
B) by adjusting the height of height adjustable seats adjustment support ring so that press-in needle point connects with without residual stress sample
It touches and is pressed into without residual stress sample point by point；
C) deformeter measures the loaded load of the process of press under without residual stress state by the strain signal that foil gauge exports,
The electromechanical impedance frequency response of piezoelectric patches on each piezoelectric beam is measured using impedance analyzer simultaneously, is pressed by electromechanical impedance frequency response
Enter the projected area of needle point and without residual stress sample, record the process of press under the without residual stress state of every bit respectively
Loaded load F and projected area S；
D) step b)~c is repeated), the F-S data that without residual stress state is pushed down into process are obtained, so as to obtain without residual stress
State is pushed down into the F-S curves of process；
E) based on least square method, according to formula F=C01S2+C02S is pushed down into without residual stress state the F-S data of process
It is fitted, obtains fitting parameter C01And C02。
5. measuring method as claimed in claim 3, which is characterized in that in step 7), residual tension can increase contact surface
Product, residual compressive stress can reduce contact area；If under the F-S curves of the process of press in of sample to be tested and without residual stress state
The F-S curves of process of press in are compared to declining, and the loaded load of residual stress is lower to have in the case of identical S values for the meaning of decline,
So residual stress is residual tension；If the F-S curves of the process of press in of sample to be tested and the pressure under without residual stress state
Enter the F-S curves of process compared to rising, the meaning of rising to there is the loaded load higher of residual stress in the case of identical S values, that
Residual stress is residual compressive stress.
6. measuring method as claimed in claim 3, which is characterized in that in step 8), the formula of residual tension isThe formula of residual compressive stress isWherein, FSFor
There are the loaded load under residual stress state, SSTo there is the contact area of press-in needle point and sample to be tested under residual stress state
Projected area, a be pressed into needle point semi-cone angle complementary angle.
7. a kind of the non-of material surface of the measuring system of material surface residual stress as described in claim 1 waits twin shafts remaining
The measuring method of stress, non-to wait in twin shafts residual stress, σx≠σy, and have σx=k σy, ratios of the k for principal stress, k ≠ 1,
It is characterized in that, the measuring method includes the following steps：
1) measuring system of material surface residual stress is completed；
2) being decomposed into the twin shafts residual stress such as non-waits biaxial stresses part and pure shear stress part to measure, and wherein pure shear should
The press-in for being pressed into needle point, which is not present, in power part influences, and the stress value size for waiting biaxial stresses part is
3) the F-S curves of the process of press under without residual stress state are obtained by without residual stress sample, so as to be fitted
Parameter C01And C02；
4) residual stress detector is fixed on to the surface of sample to be tested by multiple height adjustable seats；
5) by adjusting the height of height adjustable seats adjustment support ring so that send out in the region to be measured of press-in needle point and sample to be tested
It is raw to contact and be pressed into sample to be tested point by point；
6) loaded load F is measured using strain signal, while the machine of piezoelectric patches on each piezoelectric beam is measured using impedance analyzer
Electrical impedance frequency response is obtained the projected area S of the contact area of press-in needle point and sample to be tested by electromechanical impedance frequency response, remembered respectively
Record the loaded load F of every bit and projected area S；
7) step 5)~6 are repeated), the F-S data of the process of press in of sample to be tested are obtained, so as to obtain the press-in of sample to be tested
The F-S curves of journey；
8) the F-S curves of the process of press under the F-S curves of the process of press in of sample to be tested and without residual stress state are carried out
It compares, it is residual tension or residual compressive stress to judge residual stress；
9) according to step 9) judgement as a result, based on least square method, with reference to obtained fitting parameter C01And C02, using remnants
Tensile stress or residual compressive stress formula are fitted, and obtain the stress value size for waiting biaxial stresses part of residual stress
10) according to the ratio k of previously known principal stress, the residual stress size σ in x directions and y directions is respectively obtainedxAnd σy。
8. measuring method as claimed in claim 7, which is characterized in that in step 3), obtain under without residual stress state
The F-S curves of process of press in obtain fitting parameter C01And C02Include the following steps：
A) residual stress detector is fixed on to the surface of without residual stress sample by multiple height adjustable seats；
B) by adjusting the height of height adjustable seats adjustment support ring so that press-in needle point connects with without residual stress sample
It touches and is pressed into without residual stress sample point by point；
C) deformeter measures the loaded load of the process of press under without residual stress state by the strain signal that foil gauge exports,
The electromechanical impedance frequency response of piezoelectric patches on each piezoelectric beam is measured using impedance analyzer simultaneously, is pressed by electromechanical impedance frequency response
Enter the projected area of needle point and without residual stress sample, record the process of press under the without residual stress state of every bit respectively
Loaded load F and projected area S；
D) step b)~c is repeated), the F-S data that without residual stress state is pushed down into process are obtained, so as to obtain without residual stress
State is pushed down into the F-S curves of process；
E) based on least square method, according to formula F=C01S2+C02S is pushed down into without residual stress state the F-S data of process
It is fitted, obtains fitting parameter C01And C02。
9. measuring method as claimed in claim 7, which is characterized in that in step 8), if the process of press in of sample to be tested
F-S curves decline compared with the F-S curves of the process of press under without residual stress state, and the meaning of decline is identical S values situation
Under have the loaded load of residual stress lower, then residual stress is residual tension；If the F-S of the process of press in of sample to be tested
Curve rises compared with the F-S curves of the process of press under without residual stress state, and the meaning of rising is has in the case of identical S values
The loaded load higher of residual stress, then residual stress is residual compressive stress.
10. measuring method as claimed in claim 7, which is characterized in that in step 9), the medium biaxial stress of residual tension
Partial formula isThe formula of the medium biaxial stress part of residual compressive stress isWherein, FSTo have the loaded load under residual stress state, SSTo there is remnants
The projected area of the contact area of press-in needle point and sample to be tested under stress state, a are the complementary angle for the semi-cone angle for being pressed into needle point.
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| CN109333083B (en) * | 2018-08-22 | 2023-10-03 | 四川大学 | Residual stress detection auxiliary device for non-ferromagnetic parts |
| CN110261020A (en) * | 2019-06-18 | 2019-09-20 | 浙江工业大学 | Suitable for measuring four pressure head components of nonequiaxial residual stress |
| CN111649858B (en) * | 2020-07-13 | 2021-11-19 | 中国石油大学(华东) | Method and system for testing three-dimensional stress of residual stress of material by using nanoindentation method |
| CN111811705B (en) * | 2020-08-20 | 2022-06-24 | 浙江德元检测有限公司 | Fixing device for strain rosette and residual stress detection method using same |
| CN113358257A (en) * | 2021-06-22 | 2021-09-07 | 南京工程学院 | Drilling displacement method for measuring residual stress |
| CN114518298B (en) * | 2022-01-14 | 2023-09-29 | 东南大学 | Pressing-in calibration method for unequal double-shaft residual stress |
| CN114659692B (en) * | 2022-04-14 | 2024-04-09 | 西北稀有金属材料研究院宁夏有限公司 | Method for detecting residual stress of sample |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101206185A (en) * | 2007-10-23 | 2008-06-25 | 湘潭大学 | Method for measuring ferro-electricity membrane residual stress |
| CN102589984A (en) * | 2012-02-14 | 2012-07-18 | 北京大学 | Multi-field coupled loading micro nanometer press-in testing system and method |
| CN102759487A (en) * | 2012-07-06 | 2012-10-31 | 北京大学 | Partial stiffness method based composite material non-destructive detection system and detection method |
| CN104122331A (en) * | 2014-07-24 | 2014-10-29 | 北京大学 | Non-destructive testing system and method based on contact vibration of piezoelectric disk |
| CN104729938A (en) * | 2015-03-26 | 2015-06-24 | 北京大学 | Electromechanical impedance method-based portable hardness detection structure and detection method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101206185A (en) * | 2007-10-23 | 2008-06-25 | 湘潭大学 | Method for measuring ferro-electricity membrane residual stress |
| CN102589984A (en) * | 2012-02-14 | 2012-07-18 | 北京大学 | Multi-field coupled loading micro nanometer press-in testing system and method |
| CN102759487A (en) * | 2012-07-06 | 2012-10-31 | 北京大学 | Partial stiffness method based composite material non-destructive detection system and detection method |
| CN104122331A (en) * | 2014-07-24 | 2014-10-29 | 北京大学 | Non-destructive testing system and method based on contact vibration of piezoelectric disk |
| CN104729938A (en) * | 2015-03-26 | 2015-06-24 | 北京大学 | Electromechanical impedance method-based portable hardness detection structure and detection method thereof |
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