CN106706508A - AHP (analytic hierarchy process)-based metal material seawater corrosion sensitivity evaluation method - Google Patents

Abstract

The invention relates to an AHP (analytic hierarchy process)-based metal material seawater corrosion sensitivity evaluation method which comprises the following steps: 1. carrying out a metal material seawater corrosion test; 2. testing the corrosion rates of the metal material in different seawater regions; 3. carrying out grey correlation analysis on the corrosion rates of the metal material and environmental factors of four testing stations; and 4. evaluating the corrosion sensitivity of the metal material to different seawater factors by the AHP. The grey correlation process for comparing the influence degrees of various environmental factors is improved by the steps above, so that the contributions of seawater temperature, dissolved oxygen and other sea environment interactive factors in metal material seawater corrosion can be quantitatively described. The method is simple and convenient, and solves the problem that the metal corrosion degree of seawater factors can only be subjected to qualitative analysis comparison and can not be subjected to quantitative calculation. The obtained result can be used in sensitivity calculation of the material under different seawater factor conditions, and has important meanings for deep analysis on corrosion sensitivity of metal materials in the seawater environment.

Description

A kind of metal material seawater corrosion sensitivity assessment method based on AHP analyses

Technical field

The present invention provides a kind of metal material seawater corrosion sensitivity assessment method based on analytic hierarchy process (AHP) (i.e. AHP), Metal material is sensitive to corrosive environment of sea water factor during it is related to one kind that seawater corrosion test is calculated using AHP analytic hierarchy process (AHP)s The method of degree, belongs to analysis of material sea corrosion susceptibility method and technology field.

Background technology

In recent years, people achieve very great achievement in environmental factor on the research that soil corrosivity and atmospheric corrosiveness influence Effect.Complexity, the unstability of seawater corrosion situation due to briny environment so that Environmental Factors for Metals material seawater corrosion Property influence still be in the exploratory stage.Seawater is a kind of complicated natural balance system, in addition to containing a large amount of salts, is also contained The organic matter of dissolved oxygen, marine growth and corruption.Meanwhile, ocean temperature, flow velocity, pH value etc. all have certain influence to seawater corrosion. Therefore, marine corrosion is that a kind of corrosion presented under marine physics, Marine Chemistry and the aspect comprehensive function of marine organisms three is existing As this causes to study much more complicated than other dielectric corrosion problems of metal material marine corrosion.

Metal material long period investigation corrosion work in China's briny environment is the Ministry of Science and Technology and National Nature A long-term major project " corrosion data accumulation and rule of the material in China's typical case's natural environment supported of science fund committee A part in Journal of Sex Research ".China's seawater corrosion station net, has carried out 50 kinds of domestic common metal materials in China from nineteen eighty-three The long-term corrosion exposure test of 16 years is carried out in 4 different ocean province bands in marine site, the seawater corrosion number of a large amount of preciousnesses has been obtained According to and therefrom sum up and write the macrocyclic seawater corrosion rule of Typical Metals.

In analysis, research metal material seawater corrosion data and rule, it is related to seawater corrosion sensitive question.Environment The weight of sensitiveness and its sensitivity belongs to fuzzy concept, and it is one to carry out environmental sensitivity evaluation according to the sign of degraded performance Individual typical fuzzy diagnosis problem.Fuzzy overall evaluation is based on fuzzy mathematics, using the principle that fuzzy relation synthesizes, to incite somebody to action Some borders are difficult quantitative factor quantification, carry out a kind of method of overall merit.In material environment susceptibility comprehensive analysis In, it is related to the comprehensive function of the phenomenon of large amount of complex and many factors.And there is substantial amounts of blooming and mould in analysis Paste concept.Therefore, when environmentally sensitive property is analyzed, the method available to fuzzy overall evaluation carries out the place of quantification Reason, calculates the relative weighting of each environmental factor as the susceptibility of the environmental factor.

At present, due to influencing each other between each envirment factor and relevance, in Synthesis factors evaluation, especially to sea Aqueous corrosion determines that the weight of its each envirment factor has arbitrariness than more sensitive metal material sensitivity assessment problem, lacks More objectively determine the quantization method of envirment factor weight.There are numerous studies to pass through artificial neural network method, pattern-recongnition method Etc. analyzing corrosion prediction and corrosion regularity of the material in soil environment, atmospheric environment and briny environment.But neural network Due to being related to the continuity of pattern function, its application in some fields is limited.It is less complete that Grey Incidence is applied to information Entirely, less bright and clear system, this is consistent with the feature of seawater corrosion system.Metal material is obtained in seawater using Grey Incidence Essential environmental factors in corrosion and the degree of association between the corrosion rate in each test marine site.However, the number of these degrees of association Word in itself, in addition to the size of relatively each environmental factor to extent of corrosion, and without in all senses.Therefore, based on every weight The analytic hierarchy process (AHP) to be classified, quantitatively describes the interaction factor in the contribution of total system, is aided with the result of grey correlation analysis Polyfactorial importance degree is modified, finally by the weighted value of each factor of contribution identification correspondence, tax is weighed and is accomplished Rationally, objective and tool comparativity, calculates susceptibility of the metal material to each marine environment, is environmental data in reliability Design, checking and the effective application in assessment provide technical support.

The content of the invention

The invention aims to solve the problems, such as above-mentioned prior art, i.e., at present to metal material seawater corrosion Susceptibility there is no unified, perfect theory and method, there is provided a kind of metal material seawater corrosion susceptibility based on AHP analyses Computational methods, i.e., it is a kind of calculated using AHP analytic hierarchy process (AHP)s in seawater corrosion test metal material to corrosive environment of sea water because The method of plain susceptibility.

The purpose of the present invention is achieved through the following technical solutions：

A kind of metal material seawater corrosion sensitivity assessment method based on AHP analyses of the present invention, implementation step is as follows：

Step one, the seawater corrosion test for carrying out metal material

B10 corronils, 2A11 aluminium alloys, 2024 aluminium alloy LF11 aluminium alloys, LF3M aluminium alloys, L3M aluminium are closed first Gold, Q235 carbon steels and 16Mn low-alloy steel carry out seawater corrosion test, and all samples take from supply of material state sheet material, surface grinding, chi It is very little for 200mm × 100mm × 6~8mm. test methods are carried out according to standard GB/T 5776-1986 (meeting ISO 11306)；

The present invention chooses B10 corronils, 2A11 aluminium alloys, 2024 aluminium alloy LF11 aluminium alloys, LF3M aluminium alloys, L3M Aluminium alloy, Q235 carbon steels and 16Mn low-alloy steel are tried in Qingdao experiment station, Zhoushan experiment station, Xiamen respectively as research object Testing station and Yulin experiment station carries out seawater corrosion test；With reference to GB GB5776-1986《Ship and ocean engineering metal material Seawater corrosion test method in natural surroundings》Design corrosion test, abrasion cycle is 1 year；

Specifically carry out in the steps below：

Step 1.1, will supply of material state sheet material B10 corronils, 2A11 aluminium alloys, 2024 aluminium alloy LF11 aluminium alloys, LF3M Aluminium alloy, L3M aluminium alloys, Q235 carbon steels and 16Mn low-alloy steel are cut into the sample that size is 200mm × 100mm × 6~8mm, Per sample (p.s.) cuts 5 pieces as parallel sample, and its surface is polished；

Step 1.2, according to standard GB/T 5776-1986《Ship and ocean engineering metal material are in natural surroundings Seawater corrosion test method》(meeting ISO 11306) carries out seawater corrosion test to above sample, and experiment place is respectively green grass or young crops Island experiment station, Zhoushan experiment station, Xiamen experiment station and Yulin experiment station carry out seawater corrosion test, and abrasion cycle is 1 year；

Step 2, the corrosion rate to metal material in different seawater regions are tested

Reference standard HB5257-83 carries out corrosion rate measurement；Before carrying out seawater corrosion, prepare corrosion sample, every group will Prepare 5 parallel samples；Sample is ground on washing pre-mill, then is polished with polishing machine；Using slide measure Measure the actual size of each sample and make a record, and be cleaned by ultrasonic sample with absolute ethyl alcohol/acetone, then to cleaning after Sample is put into drying box and dries 4-6 hours, finally with the weight of electronic balance weighing each sample and records；Etch Afterwards, specimen surface corrosion product is removed according to standard HB5257-83 configuration pickles；Pickle is matched：Chromic anhybride (CrO₃) 20g, phosphoric acid (H₃PO₄Density 1.69g/cm³) 50ml, distilled water 1000ml, 15~30min of full leaching at room temperature, then Salpeter solution (HNO is immersed at room temperature₃Density 1.42g/cm³) in 15min until the corrosion product of specimen surface all removed it is dry Only；Cleaned with alcohol again afterwards, dry up after weigh corrosion after weight and record (5 samples calculate its average weightlessness)； Average corrosion rate is calculated according to formula (1)；

Wherein, M_t(mg) be corrosion after sample weight, M₀(mg) it is the initial weight of sample, A (mm²) soak entirely for sample Surface area；T (d) is etching time；

Specifically carry out in the steps below：

After step 2.1, the sample that will be corroded polishing, then it is put on water system grinder and is further ground, so It is polished with polishing machine afterwards；

Step 2.2, the sample vernier caliper measurement actual size that will be handled well simultaneously make a record；

Step 2.3, above sample is cleaned by ultrasonic with absolute ethyl alcohol or acetone and is put into 4 to 6 are dried in drying box Hour；

Step 2.4, each sample is weighed and recorded with electronic balance；

Step 2.5, above sample carries out seawater corrosion test after the completion of, acid is configured according to national standard HB5257-83 Washing lotion removes the corrosion product of each specimen surface after seawater corrosion.Pickle is matched：Chromic anhybride (CrO₃) 20g, phosphorus Acid (H₃PO₄Density 1.69g/cm³) 50ml, distilled water 1000ml, it is complete at room temperature to soak 15~30min.Again by sample that pickling is good Salpeter solution (HNO is immersed at room temperature₃Density 1.42g/cm³) in 15min until the corrosion product of specimen surface is all removed Totally；

Step 2.6, the sample for being cleaned surface corrosion product cleaned with alcohol, dry up after weigh corrosion after Weight and record (5 samples calculate its average weightlessness)；Average corrosion rate is calculated according to formula (1).

Wherein, M_t(mg) be corrosion after sample weight, M₀(mg) it is the initial weight of sample, A (mm²) soak entirely for sample Surface area；T (d) is etching time；

Step 3, the corrosion rate to metal material carry out grey correlation analysis with the environmental factor of four experiment stations

Relevant environmental data (ocean temperature, dissolved oxygen, salinity, the pH value in Qingdao, Zhoushan, Xiamen and Yulin are collected respectively And seawater velocity), the reference sequence for determining metallic material corrosion speed and the comparing ordered series of numbers for influenceing metallic material corrosion behavior are (each The environmental data ordered series of numbers in region)；Because the data in each factor row in system may be different because of dimension, be not easy to compare or than Compared with when be difficult to obtain correct conclusion；Therefore when grey relational grade analysis are carried out, the corrosion to environmental data and metal material Speed data carries out Homogenization Treatments, to eliminate the influence of dimension；Then according to above-mentioned data, to the environment of each experiment station because Incidence coefficient ξ between element and metallic material corrosion speed_iK () is calculated；Because incidence coefficient is to compare ordered series of numbers with reference Correlation degree value of the ordered series of numbers at each moment, so its several more than one, and information excessively disperses to be not easy to carry out globality Compare；It is therefore desirable to the incidence coefficient at each moment (each point i.e. in curve) is grouped as into a value, that is, introduces and calculate sea Degree of association f between foreign environmental factor and metallic material corrosion speed_i, as comparing correlation degree between ordered series of numbers and reference sequence Quantity is represented；The environmental factor bigger with the corrosion rate degree of association, its developing direction and speed are with corrosion rate closer to corruption The relation for losing speed is also tightr；

Specifically carry out in the steps below：

Step 3.1, relevant environmental data (ocean temperature, dissolved oxygen, salt that Qingdao, Zhoushan, Xiamen and Yulin are collected respectively Degree, pH value and seawater velocity).Determine the reference sequence of metallic material corrosion speed and the comparing of influence metallic material corrosion behavior Ordered series of numbers (the environmental data ordered series of numbers in each region)；

If reference sequence (also known as auxiliary sequence) be Y=Y (k) | k=1,2 ..., n }；Compare ordered series of numbers (also known as sub- sequence Row) X_i={ X_i(k) | k=1,2 ..., n }, i=1,2 ..., m；

Step 3.2, because the data in each factor row in system may be different because of dimension, be not easy to compare or when relatively It is difficult to obtain correct conclusion；Therefore when grey relational grade analysis are carried out, according to formula (2) and (3) by the ring of each experiment station Border data carry out Homogenization Treatments with the etch rate data of metal material, to eliminate the influence of dimension；

Y in formula_iIt is the equalization ordered series of numbers of each sub- factor, X_iK () is sub- factor sequence；

Y in formula₀It is the equalization ordered series of numbers of each sub- factor, X₀K () is sub- factor sequence；

Between step 3.3, environmental factor and metallic material corrosion speed according to following equation (4) to each experiment station Incidence coefficient ξ_iK () is calculated；

Step 3.4, because incidence coefficient is the correlation degree value for comparing ordered series of numbers and reference sequence at each moment, it Several more than one, and information excessively disperses to be not easy to carry out globality comparing.It is therefore desirable to by each moment (i.e. in curve Each point) incidence coefficient be grouped as a value, that is, its average value is sought, as comparing correlation degree between ordered series of numbers and reference sequence Quantity is represented.Degree of association f between Marine Environment Factors and metallic material corrosion speed is calculated according to following equation (5)_i；With corruption The bigger environmental factor of erosion Rate relating extent, its developing direction and speed are with corrosion rate closer to the relation with corrosion rate Also it is tightr；

Step 4, using AHP analytic approach to metal material to the corrosion-susceptible degree of different seawater factors

According to grey correlation analysis result, can learn that the degree of association between each environmental factor and material corrosion speed is big It is small, i.e., the close relation degree of each environmental factor and corrosion rate；It is hereby achieved that relatively important between individual environmental factor Relation, builds multilevel iudge matrix A two-by-two；To even multiplying and opening m powers per row element in A, vector is obtainedIt is right againReturned Weight vectors W is obtained after one change treatment, and then tries to achieve judgment matrix A corresponding to eigenvalue of maximum λ_maxCharacteristic vector W, through returning One change after be the sequencing weight of relative importance between environmental factor, that is, each judgment matrix each factor is relative Weight, so being substantially to calculate weight vector；Though the above-mentioned method for being configured to multilevel iudge matrix can reduce the dry of other factorses Disturb, more objectively reflect a pair of difference of Effects of Factors power；But during comprehensive whole comparative result, wherein including certain journey unavoidably The nonuniformity of degree；Therefore need to carry out consistency check to matrix A.As CR ＜ 0.1, judgment matrix is called uniformity square Battle array, it is believed that in permissible range, then each environmental factor weight assignment is correct, can be made with its characteristic vector for the inconsistent degree of matrix It is weight vector；The uniformity that the judgment matrix can tentatively be confirmed can be receiving, metal material to different briny environments because The corrosion-susceptible degree of element is the weighted value of each environmental factor, otherwise tackles judgment matrix and makees appropriate amendment；

Specifically carry out in the steps below：

Step 4.1, according to grey correlation analysis result, the pass between each environmental factor and material corrosion speed can be learnt The close relation degree of connection degree size, i.e., each environmental factor and corrosion rate.It is hereby achieved that the phase between individual environmental factor To important relationship, multilevel iudge matrix A two-by-two is built；

Step 4.2, in A per row element even multiply and open m powers, obtain vectorIt is right againAfter being normalized Obtain weight vectors W；

Step 4.3, the Maximum characteristic root λ that judgment matrix A is calculated according to following equation (6)_max；Judgment matrix A corresponds to most Big eigenvalue λ_maxCharacteristic vector W, after normalization be environmental factor between relative importance sequencing weight, that is, The relative weighting of each judgment matrix each factor, so being substantially to calculate weight vector；

AW=λ_maxW (6)

Though step 4.4, the above-mentioned method for being configured to multilevel iudge matrix can reduce the interference of other factorses, more anti- Mirror a pair of difference of Effects of Factors power；But during comprehensive whole comparative result, wherein including a certain degree of nonuniformity unavoidably； Therefore need to carry out consistency check to matrix A；Coincident indicator is calculated first Then according to following equation (7) consistency ration CR is calculated；Wherein, due to having 5 environmental factor variables, therefore RI=1.12 in the present invention；As CR ＜ When 0.1, judgment matrix is called consistency matrix, it is believed that the inconsistent degree of matrix can use its characteristic vector in permissible range As weight vector；The uniformity that the judgment matrix can tentatively be confirmed can be receiving, and metal material is to different briny environments The corrosion-susceptible degree of factor is the weighted value of each environmental factor；Otherwise reply judgment matrix makees appropriate amendment；

By above step, in the past only with Grey Incidence from the influence journey of each environmental factor of qualitatively angle changing rate Degree size is improved, and can quantitatively describe the marine environment such as ocean temperature, the dissolved oxygen interaction factor in metal material sea Contribution in aqueous corrosion, clear thinking, method are easy, and solving seawater factor can only qualitative analysis ratio to metal erosion degree Compared with, cannot quantify the problem that calculates, acquired results can be applied to during susceptibility of the material under different seawater conditions calculate, The profound analysis of corrosion-susceptible degree to metal material in briny environment is significant.

Advantage and effect

, using the analytic hierarchy process (AHP) based on every vital classification, it can be with quantitative description ocean temperature, dissolved oxygen for the present invention Deng contribution of the marine environment interaction factor in metal material seawater corrosion, it is aided with the result of grey correlation analysis to marine environment The importance degree of the factor is modified, and finally by the weighted value of each ocean factor of contribution identification correspondence, is weighed tax and is accomplished Rationally, objective and tool comparativity, clear thinking, method are easy, and solving seawater factor can only qualitative point to metal erosion degree Analysis compares, cannot quantify the problem for calculating, and the profound analysis of the corrosion-susceptible degree to metal material in briny environment has weight Want meaning.

Brief description of the drawings

Fig. 1 the method for the invention flow charts.

Specific embodiment

The metal material seawater corrosion sensitivity assessment method based on AHP involved by the present embodiment, as shown in Figure 1.This A kind of metal material seawater corrosion sensitivity assessment method based on AHP of invention, specific implementation step is as follows：

Step one, the seawater corrosion test of metal material

Step 1.1, will supply of material state sheet material B10 corronils, 2A11 aluminium alloys, 2024 aluminium alloy LF11 aluminium alloys, LF3M Aluminium alloy, L3M aluminium alloys, Q235 carbon steels and 16Mn low-alloy steel are cut into the sample that size is 200mm × 100mm × 6~8mm, Per sample (p.s.) cuts 5 pieces as parallel sample, and its surface is polished.

Step 1.2, according to standard GB/T 5776-1986《Ship and ocean engineering metal material are in natural surroundings Seawater corrosion test method》(meeting ISO 11306) carries out seawater corrosion test to above sample, and experiment place is respectively green grass or young crops Island experiment station, Zhoushan experiment station, Xiamen experiment station and Yulin experiment station carry out seawater corrosion test, and abrasion cycle is 1 year

Step 2, the corrosion rate to metal material in different seawater regions are tested

After step 2.1, the sample that will be corroded polishing, then it is put on water system grinder and is further ground, so It is polished with polishing machine afterwards.

Step 2.2, the sample vernier caliper measurement actual size that will be handled well simultaneously make a record.

Step 2.3, above sample is cleaned by ultrasonic with absolute ethyl alcohol or acetone and is put into 4 to 6 are dried in drying box Hour.

Step 2.4, each sample is weighed and recorded with electronic balance.

Step 2.5, above sample carries out seawater corrosion test after the completion of, acid is configured according to national standard HB5257-83 Washing lotion removes the corrosion product of each specimen surface after seawater corrosion.Pickle is matched：Chromic anhybride (CrO₃) 20g, phosphorus Acid (H₃PO₄Density 1.69g/cm³) 50ml, distilled water 1000ml, it is complete at room temperature to soak 15~30min.Again by sample that pickling is good Salpeter solution (HNO is immersed at room temperature₃Density 1.42g/cm³) in 15min until the corrosion product of specimen surface is all removed Totally.

Step 2.6, the sample for being cleaned surface corrosion product cleaned with alcohol, dry up after weigh corrosion after Weight and record (5 samples calculate its average weightlessness)；Average corrosion rate is calculated according to formula (1).

Wherein, M_t(mg) be corrosion after sample weight, M₀(mg) it is the initial weight of sample, A (mm²) soak entirely for sample Surface area；T (d) is etching time.

Step 3, the corrosion rate to metal material carry out grey correlation analysis with the environmental factor of four experiment stations

Step 3.1, relevant environmental data (ocean temperature, dissolved oxygen, salt that Qingdao, Zhoushan, Xiamen and Yulin are collected respectively Degree, pH value and seawater velocity).Determine the reference sequence of metallic material corrosion speed and the comparing of influence metallic material corrosion behavior Ordered series of numbers (the environmental data ordered series of numbers in each region).

If reference sequence (also known as auxiliary sequence) be Y=Y (k) | k=1,2 ..., n }；Compare ordered series of numbers (also known as sub- sequence Row) X_i={ X_i(k) | k=1,2 ..., n }, i=1,2 ..., m.

Step 3.2, because the data in each factor row in system may be different because of dimension, be not easy to compare or when relatively It is difficult to obtain correct conclusion.Therefore when grey relational grade analysis are carried out, according to formula (2) and (3) by the ring of each experiment station Border data carry out Homogenization Treatments with the etch rate data of metal material, to eliminate the influence of dimension.

Y in formula_iIt is the equalization ordered series of numbers of each sub- factor, X_iK () is sub- factor sequence；

Y in formula₀It is the equalization ordered series of numbers of each sub- factor, X₀K () is sub- factor sequence.

Associating between step 3.3, environmental factor and metallic material corrosion speed according to formula (4) to each experiment station Coefficient ξ_iK () is calculated.

Step 3.4, because incidence coefficient is the correlation degree value for comparing ordered series of numbers and reference sequence at each moment, it Several more than one, and information excessively disperses to be not easy to carry out globality comparing.It is therefore desirable to by each moment (i.e. in curve Each point) incidence coefficient be grouped as a value, that is, its average value is sought, as comparing correlation degree between ordered series of numbers and reference sequence Quantity is represented.Degree of association f between Marine Environment Factors and metallic material corrosion speed is calculated according to formula (5)_i.With corrosion speed The bigger environmental factor of the rate degree of association, its developing direction and speed are with corrosion rate closer to the relation with corrosion rate is also got over Closely.

Step 4, using AHP analytic approach to metal material to the corrosion-susceptible degree of different seawater factors

Step 4.1, according to grey correlation analysis result, the pass between each environmental factor and material corrosion speed can be learnt The close relation degree of connection degree size, i.e., each environmental factor and corrosion rate.It is hereby achieved that the phase between individual environmental factor To important relationship, multilevel iudge matrix A two-by-two is built；

Step 4.2, in A per row element even multiply and open m powers, obtain vectorIt is right againAfter being normalized Obtain weight vectors W；

Step 4.3, the Maximum characteristic root λ that judgment matrix A is calculated according to following equation (6)_max；Judgment matrix A corresponds to most Big eigenvalue λ_maxCharacteristic vector W, after normalization be environmental factor between relative importance sequencing weight, that is, The relative weighting of each judgment matrix each factor, so being substantially to calculate weight vector；

AW=λ_maxW (6)；

Though step 4.4, the above-mentioned method for being configured to multilevel iudge matrix can reduce the interference of other factorses, more anti- Mirror a pair of difference of Effects of Factors power；But during comprehensive whole comparative result, wherein including a certain degree of nonuniformity unavoidably； Therefore need to carry out consistency check to matrix A, coincident indicator is calculated first Then according to following equation (7) consistency ration CR is calculated.Wherein, due to having 5 environmental factor variables, therefore RI=1.12 in the present invention.As CR ＜ When 0.1, judgment matrix is called consistency matrix, it is believed that the inconsistent degree of matrix can use its characteristic vector in permissible range As weight vector；The uniformity that the judgment matrix can tentatively be confirmed can be receiving, and metal material is to different briny environments The corrosion-susceptible degree of factor is the weighted value of each environmental factor.Otherwise reply judgment matrix makees appropriate amendment；

The present invention quantitatively describes the seas such as ocean temperature, dissolved oxygen using the analytic hierarchy process (AHP) based on every vital classification Contribution of the foreign environmental interaction factor in metal material seawater corrosion, is aided with the result of grey correlation analysis to the marine environment factor Importance degree modify, finally by contribution identification correspondence each ocean factor weighted value, make tax weigh accomplish rationally, Objective and tool comparativity, clear thinking, method are easy, and solving seawater factor can only qualitative analysis ratio to metal erosion degree Compared with, the problem that calculates cannot be quantified, to metal material, the profound analysis of corrosion-susceptible degree in briny environment has important meaning Justice.

Claims (5)

1. it is a kind of based on AHP analysis metal material seawater corrosion sensitivity assessment method, it is characterised in that：Implementation step is such as Under：

Step one, the seawater corrosion test for carrying out metal material；

Step 2, the corrosion rate to metal material in different seawater regions are tested；

Step 3, the corrosion rate to metal material carry out grey correlation analysis with the environmental factor of four experiment stations；

Step 4, using AHP analytic approach to metal material to the corrosion-susceptible degree of different seawater factors；

By above step, in the past big from the influence degree of each environmental factor of qualitatively angle changing rate only with Grey Incidence It is small to be improved, can quantitatively describe ocean temperature and dissolved oxygen these marine environment interaction factor is rotten in metal material seawater Contribution in erosion, clear thinking, method are easy, solve seawater factor to metal erosion degree can only qualitative analysis compare, nothing The problem that standard measure is calculated, acquired results can apply in susceptibility calculating of the material under different seawater conditions, to gold The profound analysis of corrosion-susceptible degree of the category material in briny environment is significant.

2. a kind of metal material seawater corrosion sensitivity assessment method based on AHP analyses according to claim 1, it is special Levy and be：" carrying out the seawater corrosion test of metal material " described in step one, its practice is as follows：

Step 1.1：Will supply of material state sheet material B10 corronils, 2A11 aluminium alloys, 2024 aluminium alloy LF11 aluminium alloys, the conjunction of LF3M aluminium Gold, L3M aluminium alloys, Q235 carbon steels and 16Mn low-alloy steel are cut into the sample that size is 200mm × 100mm × 6~8mm, every kind of Sample cuts 5 pieces as parallel sample, and its surface is polished；

Step 1.2：According to standard GB/T 5776-1986《The sea of ship and ocean engineering metal material in natural surroundings Aqueous corrosion test method》Seawater corrosion test is carried out to above sample, experiment place is respectively Qingdao experiment station, Zhoushan experiment Stand, Xiamen experiment station and Yulin experiment station carry out seawater corrosion test, abrasion cycle is 1 year.

3. a kind of metal material seawater corrosion sensitivity assessment method based on AHP analyses according to claim 1, it is special Levy and be：" corrosion rate to metal material in different seawater regions is tested " described in step 2, its practice is such as Under：

Step 2.1：After the sample polishing that will be corroded, then it is put on water system grinder and is further ground, Ran Houyong Polishing machine is polished；

Step 2.2：The sample vernier caliper measurement actual size that to handle well simultaneously makes a record；

Step 2.3：Above sample is cleaned by ultrasonic and is put into drying box with the one kind in absolute ethyl alcohol and acetone and dried 4 to 6 hours；

Step 2.4：Each sample is weighed and recorded with electronic balance；

Step 2.5：After the completion of above sample carried out into seawater corrosion test, pickle is configured according to national standard HB5257-83 To remove the corrosion product of each specimen surface after seawater corrosion；Pickle is matched：Chromic anhybride (CrO₃) 20g, phosphoric acid (H₃PO₄Density 1.69g/cm³) 50ml, distilled water 1000ml, it is complete at room temperature to soak 15~30min；The good sample of pickling is existed again 15min in salpeter solution is immersed at room temperature until the corrosion product of specimen surface is all removed totally；

Step 2.6：The sample that surface corrosion product is cleaned cleaned with alcohol, dry up after weigh the weight after corrosion Measure and record, 5 samples calculate its average weightlessness；Average corrosion rate is calculated according to formula (1)；

$v=\frac{|M_t-M_0|}{A\×T}---\left(1\right)$

Wherein, M_t(mg) be corrosion after sample weight, M₀(mg) it is the initial weight of sample, A (mm²) surface is soaked entirely for sample Product；T (d) is etching time.

4. a kind of metal material seawater corrosion sensitivity assessment method based on AHP analyses according to claim 1, it is special Levy and be：" grey pass is carried out to the corrosion rate of metal material and the environmental factor of four experiment stations described in step 3 Connection analysis ", its practice is as follows：

Step 3.1：Collect the environmental data in Qingdao, Zhoushan, Xiamen and Yulin respectively, that is, have ocean temperature, dissolved oxygen, salinity, The data of pH value and seawater velocity；Determine the reference sequence of metallic material corrosion speed and the ratio of influence metallic material corrosion behavior Compared with the environmental data ordered series of numbers that ordered series of numbers is each region；

If reference sequence, also known as auxiliary sequence, be Y=Y (k) | k=1,2 ..., n；Compare ordered series of numbers, also known as subsequence X_i= {X_i(k) | k=1,2 ..., n }, i=1,2 ..., m；

Step 3.2：Due to the data in each factor row in system because dimension is different, it is not easy to compare and be difficult to when relatively to obtain Correct conclusion, therefore when grey relational grade analysis are carried out, according to formula (2) and (3) by the environmental data of each experiment station and The etch rate data of metal material carries out Homogenization Treatments, to eliminate the influence of dimension；

$\begin{array}{ccc}{Y}_i=\frac{X_i\left(k\right)}{\frac{1}{m}\underset{k=1}{\overset{m}{\Σ}}{X}_i\left(k\right)}& i=1,2,3,4,5;& k=1,2,3,4,\end{array}---\left(3\right)$

Y in formula_iIt is the equalization ordered series of numbers of each sub- factor, X_iK () is sub- factor sequence；

$\begin{array}{cc}{Y}_0=\frac{X_0\left(k\right)}{\frac{1}{m}\underset{k=1}{\overset{m}{\Σ}}{X}_0\left(k\right)}& k=1,2,3,.4,\end{array}---\left(3\right)$

Y in formula₀It is the equalization ordered series of numbers of each sub- factor, X₀K () is sub- factor sequence；

Step 3.3：Associating between the environmental factor and metallic material corrosion speed according to following equation (4) to each experiment station Coefficient ξ_iK () is calculated；

${\mathrm{\ξ}}_i\left(k\right)=\frac{\underset{i}{\min }\underset{k}{\min }|Y_0\left(k\right)-Y_i\left(k\right)|+\mathrm{\α}\underset{i}{\max }\underset{k}{\max }|Y_0\left(k\right)-Y_i\left(k\right)|}{|Y_0\left(k\right)-Y_i\left(k\right)|+\mathrm{\α}\underset{i}{\max }\underset{k}{\max }|Y_0\left(k\right)-Y_i\left(k\right)|}---\left(4\right)$

Step 3.4：Because incidence coefficient is to compare ordered series of numbers and correlation degree value of the reference sequence at each moment, its number More than one, and information excessively disperses to be not easy to carry out globality comparing；It is therefore desirable to be each in curve by each moment The incidence coefficient of point is grouped as a value, that is, its average value is sought, as the quantity for comparing correlation degree between ordered series of numbers and reference sequence Represent；Degree of association f between Marine Environment Factors and metallic material corrosion speed is calculated according to following equation (5)_i；With corrosion speed The bigger environmental factor of the rate degree of association, its developing direction and speed are with corrosion rate closer to the relation with corrosion rate is also got over Closely；

$\begin{array}{cc}{f}_i=\frac{1}{m}\underset{i=1}{\overset{m}{\Σ}}{\mathrm{\ξ}}_i\left(k\right)& k=1,2,3,4\end{array}---\left(5\right).$

5. a kind of metal material seawater corrosion sensitivity assessment method based on AHP analyses according to claim 1, it is special Levy and be：" using AHP analytic approach to metal material to the corrosion-susceptible degree of different seawater factors " described in step 4, its The practice is as follows：

Step 4.1：According to grey correlation analysis result, can learn that the degree of association between each environmental factor and material corrosion speed is big It is small, i.e., the close relation degree of each environmental factor and corrosion rate；Thus the relatively important relation between an environmental factor is obtained, Build multilevel iudge matrix A two-by-two；

Step 4.2：To even multiplying and opening m powers per row element in A, vector is obtainedIt is right againObtained after being normalized Weight vectors W；

Step 4.3：The Maximum characteristic root λ of judgment matrix A is calculated according to following equation (6)_max；Judgment matrix A corresponds to maximum special Value indicative λ_maxCharacteristic vector W, the sequencing weight of relative importance between environmental factor is after normalization, it is that is, each The relative weighting of individual each factor of judgment matrix, so being substantially to calculate weight vector；

AW=λ_maxW (6)；

Step 4.4：Though the above-mentioned method for being configured to multilevel iudge matrix can reduce the interference of other factorses, more objectively reflect A pair of difference of Effects of Factors power；But during comprehensive whole comparative result, wherein including a certain degree of nonuniformity unavoidably；Therefore Need to carry out consistency check to matrix A, coincident indicator is calculated firstThen according to following equation (7) Calculate consistency ration CR；Wherein, due to having 5 environmental factor variables, therefore RI=1.12 in the present invention；As CR ＜ 0.1 When, judgment matrix is called consistency matrix, it is believed that the inconsistent degree of matrix can use its characteristic vector conduct in permissible range Weight vector；The uniformity that the judgment matrix can tentatively be confirmed is receptible, and metal material is to different marine environments Corrosion-susceptible degree is the weighted value of each environmental factor；Otherwise reply judgment matrix makees appropriate amendment；

$CR=\frac{CI}{RI}---\left(7\right).$