A method and system for analyzing the composition design of a high-strength steel with low susceptibility to liquid metal embrittlement

Abstract

The application discloses a kind of high-strength steel component design analysis method and system of low liquid metal embrittlement sensitivity, adopt galvanized high-strength steel component system design criterion, combine the data information in the solute distribution coefficient of the chemical composition of existing high-strength steel matrix, high-strength steel matrix element and zinc element mixing enthalpy, element in high-strength steel matrix, define and propose high-strength steel liquid metal embrittlement sensitivity index, and based on the formula for calculating liquid metal embrittlement sensitivity index, the liquid metal embrittlement sensitivity index of different components of high-strength steel is counted and calculated, the boundary value that high-strength steel liquid metal embrittlement sensitivity meets actual requirement is obtained, the high-strength steel component that meets low liquid metal embrittlement sensitivity standard is obtained, for low liquid metal embrittlement sensitivity galvanized high-strength steel component design.The application can quantitatively evaluate the liquid metal embrittlement sensitivity of galvanized high-strength steel, be applied to the technical field of high-strength steel for automobile, guide and design low LME sensitivity advanced high-strength steel.

Description

TECHNICAL FIELD

[0001] The application relates to a high-strength steel component design analysis method and system, and applies to the technical field of high-strength steel for automobiles. BACKGROUND

[0002] In recent years, the increasingly serious environmental problems such as energy shortage, air pollution and global warming have made countries and fields pay more and more attention to energy saving and carbon emission reduction, which has put forward new requirements and challenges to the energy saving and emission reduction of the automobile industry. At present, the design concept of automobile "green manufacturing" is proposed to effectively reduce the harm to the environment and achieve the purpose of automobile lightweight as much as possible. The global strategy of energy saving and environmental protection puts forward higher and higher requirements for automobile lightweight, which not only needs to reduce the weight of the automobile body, but also needs to ensure the safety of the automobile body. The research and development of lightweight materials are of great significance to the sustainable development of the automobile industry, which not only relates to the energy saving, emission reduction, safety, cost and many other aspects of vehicles, but also is extremely important to the world energy, natural resources and environmental protection, and has become the leading direction of the development of automobile material technology. Major automobile manufacturers at home and abroad have been committed to improving the high strength and lightweight of the body framework structure, and the high-strength material represented by advanced high-strength steel (AHSS) has fully shown the great potential of realizing energy saving by reducing the weight of the automobile.

[0003] With the advancement of automobile lightweight process, automobile enterprises have more and more demand for ultra-high strength steel. Hot forming technology has obvious advantages in solving the problems of poor shape and high forming load during cold working of high-strength steel sheet. In order to prevent oxidation of the surface of the steel sheet during heating and at the same time obtain good corrosion resistance, galvanizing processes including hot-dip galvanizing, electroplating zinc, and galvannealing are widely used. The application of galvanized high-strength steel in the automobile field inevitably needs to use connection technology. Resistance spot welding has the advantages of fast speed and low cost, and has become the main connection technology for splicing automobile body structure parts. The quality of the welding spot directly affects the strength, impact resistance and other properties of the automobile body, and is an important indicator for measuring the safety of the automobile body. However, the liquid metal embrittlement (LME) phenomenon is easy to occur during the subsequent hot working such as hot stamping and spot welding of galvanized high-strength steel, which becomes an important obstacle for the application of galvanized high-strength steel in the automobile field.

[0004] The typical galvanized high-strength steels such as dual-phase (DP), transformation induced plasticity (TRIP), twinning induced plasticity (TWIP) and quenching and partitioning (QP) steels will all produce LME phenomenon during hot stamping and resistance spot welding, covering three generations of high-strength steels for automobiles, among which TWIP and QP steels have higher LME crack sensitivity. This will undoubtedly have a very negative impact on the safety of galvanized automobile sheets in the application process. Reasonable spot welding process adjustment and element control can to some extent reduce the LME cracks of galvanized high-strength steels, but it is difficult to fundamentally solve the LME problem.

[0005] The applicant of the present application has searched the foreign scientific and technological databases such as Engineering Index (EI), Sciencedirect, ISI Web of Science, Chinese Journal Net and Chinese VIP Chinese Journal Database using the keywords of liquid metal embrittlement + composition design, and no completely relevant documents have been found. The applicant has also searched the United States Patent and Trademark Office (USPTO), the European Patent Office (EPO), the World Intellectual Property Organization (WIPO), China Patent Information Network and the State Intellectual Property Office of the People's Republic of China, and no similar patents have been found. SUMMARY

[0006] In order to solve the technical problem that the prior art and means cannot accurately or quantitatively evaluate the LME sensitivity of galvanized high-strength steels, the purpose of the present application is to overcome the deficiencies of the existing technology, and to provide a composition design analysis method and system for high-strength steels with low liquid metal embrittlement sensitivity. The present application adopts advanced high-strength steel composition system design criteria with low LME sensitivity, combines factors such as chemical composition, mixing enthalpy and solute distribution coefficient, defines and proposes an advanced high-strength steel LME sensitivity index S LME , and based on the formula of the LME sensitivity index, the LME sensitivity index of advanced galvanized high-strength steels with different compositions is calculated, the boundary value of the LME sensitivity of advanced high-strength steels meeting the actual requirements is obtained, and this is used as the theoretical basis to guide and design advanced high-strength steels with low LME sensitivity.

[0007] In order to achieve the above-mentioned purposes, the present application adopts the following technical solutions:

[0008] A high-strength steel composition design analysis method with low liquid metal embrittlement sensitivity adopts the following composition system design criteria for galvanized high-strength steel:

[0009] In combination with the data information of the chemical composition of the existing high-strength steel substrate, the mixing enthalpy of the high-strength steel substrate elements and zinc elements, and the solute distribution coefficient of part of the elements in the high-strength steel substrate, a high-strength steel liquid metal embrittlement (LME) sensitivity index S is defined and proposed LME , and based on the formula for calculating the liquid metal embrittlement (LME) sensitivity index, the liquid metal embrittlement (LME) sensitivity index of high-strength steel with different compositions is calculated and calculated, and the boundary value of the liquid metal embrittlement (LME) sensitivity of high-strength steel that meets the actual requirements is obtained, thereby obtaining the composition of high-strength steel that meets the low liquid metal embrittlement sensitivity standard, which is used for the composition design of galvanized high-strength steel with low liquid metal embrittlement (LME) sensitivity;

[0010] The formula for calculating the liquid metal embrittlement (LME) sensitivity index is as follows:

[0011] S LME =∑w i ×M i ×(1-k i );

[0012] Where i is the element, w i is the mass percentage of the corresponding i-th element, which is the value after multiplying the actual content percentage by 100, M i is the mixing enthalpy of the i-th element and Zn element, with the unit of kJ / mol, k i is the solute distribution coefficient of the i-th element in the iron matrix, 0<k i <1.

[0013] Preferably, when calculating the liquid metal embrittlement (LME) sensitivity index of high-strength steel with different compositions based on the formula for calculating the liquid metal embrittlement (LME) sensitivity index, the following analysis method is adopted:

[0014] Based on the formula for calculating the liquid metal embrittlement (LME) sensitivity index, the liquid metal embrittlement (LME) sensitivity index S LME of high-strength steel with different compositions is calculated, and then the calculation results of high-strength steel with different compositions are compared:

[0015] (1) When S LME <-17kJ / mol, the corresponding high-strength steel has a steel composition with a serious LME tendency;

[0016] (2) When -17kJ / mol<S LME<15 kJ / mol, the corresponding high-strength steel has a high LME tendency of steel composition;

[0017] (3) when S LME <15 kJ / mol, the corresponding high-strength steel has a small LME tendency of steel composition;

[0018] Based on the results obtained in (3), the standard requirements of high-strength steel composition satisfying low liquid metal embrittlement sensitivity are determined.

[0019] Preferably, the low liquid metal embrittlement sensitivity high-strength steel composition design analysis method of the present application is characterized in that it comprises the following steps:

[0020] a. Determine and obtain at least one of the chemical composition of different high-strength steels to be analyzed, the mixing enthalpy of high-strength steel matrix elements and zinc elements, and the solute distribution coefficient of part of the elements in the high-strength steel matrix;

[0021] b. Calculate the LME sensitivity index of the advanced high-strength steel using the formula of the liquid metal embrittlement (LME) sensitivity index respectively, using the following calculation method:

[0022] The formula of the liquid metal embrittlement (LME) sensitivity index is as follows:

[0023] S LME =∑w i ×M i ×(1-k i );

[0024] Where i is an element, w i is the mass percentage of the corresponding i-th element, which is the value after multiplying the actual content percentage by 100, M i is the mixing enthalpy of the i-th element and Zn element, with the unit of kJ / mol, k i is the solute distribution coefficient of the i-th element in the iron matrix, 0<k i <1;

[0025] c. Based on the formula for calculating the liquid metal embrittlement (LME) sensitivity index, the liquid metal embrittlement (LME) sensitivity index S LME of high-strength steels with different compositions is calculated to obtain the calculation results of high-strength steels with different compositions, and then compared:

[0026] (1) when S LME <15 kJ / mol, the corresponding high-strength steel has a high LME tendency of steel composition;

[0027] (2) when -17kJ / mol<S LMEWhen the value is less than -15 kJ / mol, the corresponding high-strength steel has a steel composition with a higher tendency for LME (Limited Metal Equilibrium).

[0028] (3) When S LME When the value is >-15 kJ / mol, the corresponding high-strength steel has a steel composition with a smaller tendency for LME.

[0029] Based on the results obtained in (3), the standard requirements for high-strength steel composition that meets the low liquid metal embrittlement sensitivity were determined, and the S value for high-strength steel with liquid metal embrittlement (LME) sensitivity that meets the actual requirements was obtained. LME Boundary values.

[0030] Preferably, the high-strength steel of the present invention includes quenching and partitioning (QP) steel, twinning induced plasticity (TWIP) steel, dual-phase (DP) steel, and other high-strength steel systems that have a tendency to produce LME.

[0031] Preferred, the steel composition of this high-strength steel includes at least one element selected from C, Si, Mn, and Al that can exist in steel.

[0032] Preferably, the steel composition range of the high-strength steel, calculated by mass percentage, is as follows:

[0033] C≤0.12%; Si≤0.5%; Mn: 0.3-2.7%; Mo≤0.5%; Al≤0.015%; Nb≤0.035%; Ti≤0.03%;

[0034] P≤0.015%; S≤0.001%; ​​the remainder is Fe and unavoidable impurities.

[0035] Preferably, for the calculated high-strength steel liquid metal embrittlement (LME) sensitivity index S LME The value of S obtained through calculation LME The more negative the value, the higher the sensitivity of the corresponding high-strength steel to liquid metal embrittlement (LME), that is, the more prone it is to producing liquid metal embrittlement (LME) cracks.

[0036] Preferably, in step c, the resistance spot welding and thermoforming are based on existing process parameters. The LME sensitivity assessment includes the LME crack location and crack length.

[0037] Preferably, for high-strength steel plates, the length of the liquid metal embrittlement (LME) crack in high-strength steel that meets the low liquid metal embrittlement sensitivity standard is no more than 10% of the thickness of the high-strength steel plate.

[0038] More preferably, the length of the liquid metal embrittlement (LME) crack in the high-strength steel that meets the low liquid metal embrittlement sensitivity standard is no greater than 4.1% of the thickness of the high-strength steel plate.

[0039] A high-strength steel composition design and analysis system with low sensitivity to liquid metal embrittlement, which executes the program of the high-strength steel composition design and analysis method with low sensitivity to liquid metal embrittlement described in this invention, is characterized by including an input module, a data analysis and processing module, an output module, and a storage module;

[0040] The input module is used to input information on the composition content of different high-strength steels to be analyzed, the enthalpy of mixing of the matrix elements and zinc elements of the high-strength steel, and the solute partition coefficient data of some elements in the high-strength steel matrix.

[0041] The data analysis and processing module executes a computer program for designing and analyzing the composition of high-strength steel with low sensitivity to liquid metal embrittlement.

[0042] The output module outputs the design analysis results of high-strength steel with low sensitivity to liquid metal embrittlement.

[0043] The storage module is used to store data from computer programs and computational analysis processes.

[0044] This invention adopts the design criteria for advanced high-strength steel composition systems with low LME sensitivity, and combines factors such as chemical composition, enthalpy of mixing, and solute partition coefficient to define and propose the LME sensitivity index S for advanced high-strength steel. LME Based on the formula of LME sensitivity index, the LME sensitivity index of advanced galvanized high-strength steel with different compositions was statistically calculated, and the boundary value of LME sensitivity of advanced high-strength steel meeting the actual requirements was obtained. Based on this, advanced high-strength steel with low LME sensitivity was designed.

[0045] Compared with the prior art, the present invention has the following obvious and prominent substantive features and significant advantages:

[0046] 1. This invention, by combining factors such as chemical composition, enthalpy of mixing, and solute partition coefficient, defines and proposes an advanced high-strength steel LME sensitivity index S. LME Based on the formula of the LME sensitivity index, the sensitivity of galvanized high-strength steel to liquid metal embrittlement (LME) can be quantitatively assessed.

[0047] 2. This invention is applicable to the quantitative assessment of LME sensitivity of various types of high-strength steels used in automobiles, and guides the design of advanced high-strength steels with low LME sensitivity. Attached Figure Description

[0048] Figure 1 This is an image showing the LME crack observation results of QP980 high-strength steel in Embodiment 1 of the present invention.

[0049] Figure 2 Figure 2 is a graph of the observation results of LME cracks of the TWIP 950 high-strength steel of the second embodiment of the present application.

[0050] Figure 3 Figure 3 is a graph of the observation results of LME cracks of the DP1180 high-strength steel of the third embodiment of the present application.

[0051] Figure 4 Figure 4 is a graph of the observation results of LME cracks of the IF steel of the fourth embodiment of the present application. DETAILED DESCRIPTION

[0052] The above scheme is further described in combination with specific embodiments, and the preferred embodiments of the present application are described in detail as follows:

[0053] Embodiment 1

[0054] In this embodiment, a component design analysis method of a high-strength steel with low liquid metal embrittlement sensitivity includes the following steps:

[0055] (1) QP980 high-strength steel obtained by using an existing hot galvanizing process is selected to determine its chemical composition; the chemical composition table is shown in Table 1, the mixing enthalpy of Zn element and related elements is shown in Table 2, and the solute distribution coefficient of typical elements in the steel is shown in Table 3;

[0056] Table 1. Chemical composition table of QP980 high-strength steel (wt. %)

[0057]

[0058] Table 2. Mixing enthalpy of Zn element and related elements

[0059]

[0060] Table 3. Solute distribution coefficient of typical elements in the steel

[0061]

[0062] (2) The LME sensitivity index S of the QP980 high-strength steel is calculated by using the LME sensitivity index formula, and the calculation result is -21.29 kJ / mol, which indicates that the steel has serious LME sensitivity S <-17 kJ / mol. LME LME

[0063] Test analysis:

[0064] ​​The corresponding spot welding joints are obtained under the resistance spot welding process conditions respectively, the resistance spot welding samples are cut by a wire cutting machine, the samples containing all the welding feature areas of the spot welding joints are cut off, the cut-off samples are surface washed to prevent foreign matters from interfering with the test results, and the washed samples are dried;

[0065] Then the dried samples are ground and polished, the ground and polished samples are photographed under a metallographic microscope to obtain the morphology pictures of the ground and polished surfaces, as shown in Figure 1 Figure 1 (a) and (b) are LME cracks in the shoulder of the spot of the QP980 high-strength steel resistance spot welding joint. The LME crack length is measured by metallography, and the maximum crack length observed is 152.2 μm, which exceeds 10% of the plate thickness 1.4 mm, and does not meet the standard requirements.

[0066] Example Two:

[0067] This example is basically the same as Example One, and the particularity lies in that:

[0068] In this example, a high-strength steel composition design analysis method with low liquid metal embrittlement sensitivity includes the following steps:

[0069] (1) TWIP950 high-strength steel obtained by using existing hot galvanizing process is selected to determine its chemical composition. The chemical composition table is shown in Table 4; the mixing enthalpy of Zn element and related elements is shown in Table 5, and the solute distribution coefficient of typical elements in the steel is shown in Table 6;

[0070] Table 4. Chemical composition table of TWIP950 high-strength steel (wt. %)

[0071]

[0072] Table 5. Mixing enthalpy of Zn element and related elements

[0073]

[0074] Table 6. Solute distribution coefficient of typical elements in the steel

[0075]

[0076] (2) The LME sensitivity index S of TWIP950 high-strength steel is calculated by using the LME sensitivity index formula, and the calculation result is -47.7 kJ / mol, which indicates that the steel has serious LME sensitivity S <-17 kJ / mol. LME LME

[0077] Test analysis:

[0078] ​​​Under resistance spot welding conditions, corresponding spot welded joints were obtained. The resistance spot welded samples were wire-cut to cut out samples containing all welding feature areas of the spot welded joint. The cut samples were then surface-washed to prevent interference from foreign objects on the test results. The washed samples were then dried. The dried samples were then polished. After polishing, the samples were photographed under a metallographic microscope to obtain images of the polished surface morphology, such as... Figure 2 As shown;

[0079] Metallographic measurement of the LME crack length showed that the maximum crack length was 1076.45 μm, which exceeded the plate thickness of 1.4 mm by 10% and did not meet the standard requirements.

[0080] Example 3:

[0081] This embodiment is basically the same as the previous embodiments, except that:

[0082] In this embodiment, a method for designing and analyzing the composition of high-strength steel with low embrittlement sensitivity in liquid metals includes the following steps:

[0083] (1) Select DP1180 high-strength steel obtained using the existing hot-dip galvanizing process and determine its chemical composition. The chemical composition table is shown in Table 7; the enthalpy of mixing of Zn and related elements is shown in Table 8; and the solute partition coefficients of typical elements in the steel are shown in Table 9.

[0084] Table 7. Chemical composition of DP1180 high-strength steel (wt.%)

[0085]

[0086] Table 8. Enthalpy of mixture of Zn and related elements

[0087]

[0088] Table 9. Solute partition coefficients of typical elements in steel

[0089]

[0090] (2) Using the LME sensitivity index formula to evaluate the LME sensitivity index S of DP1180 high-strength steel. LME Calculations were performed, and the result was -11.8 kJ / mol, indicating that this steel grade has low LME sensitivity. LME >-15kJ / mol.

[0091] Experimental test analysis:

[0092] The corresponding spot welding joint is obtained under the condition of resistance spot welding process. The resistance spot welding sample is cut by wire cutting, and the sample containing all welding feature areas of the spot welding joint is cut off. The cut sample is surface washed to prevent foreign matter from interfering with the test result. The washed sample is dried. The dried sample is ground and polished. The ground and polished sample is photographed under a metallographic microscope to obtain the morphology picture of the ground and polished surface. Referring to Figure 3 ; wherein, Figure 3 (a) and (b) are LME cracks of the shoulder of the spot of the DP1180 high-strength steel resistance spot welding joint.

[0093] The maximum crack length observed by the metallographic measurement of the LME crack length is 56.3 μm, which is lower than 10% of the thickness of 1.4 mm, and meets the standard requirement.

[0094] Example Four

[0095] This example is basically the same as the foregoing examples, and the particularity lies in that:

[0096] In this example, a high-strength steel composition design analysis method with low liquid metal embrittlement sensitivity includes the following steps:

[0097] (1) Selecting an IF low-alloy steel obtained by using an existing hot-dip galvanizing process, the chemical composition of the steel is determined. The chemical composition table is shown in Table 10; the mixing enthalpy of Zn element and related elements is shown in Table 11; and the solute distribution coefficient of typical elements in the steel is shown in Table 12.

[0098] Table 10. Chemical composition table of IF steel (wt. %)

[0099]

[0100] Table 11. Mixing enthalpy of Zn element and related elements

[0101]

[0102] Table 12. Solute distribution coefficient of typical elements in the steel

[0103]

[0104] (2) The LME sensitivity index S of the IF steel is calculated by using the LME sensitivity index formula, and the calculation result is -0.8 kJ / mol. It is judged that the steel has a lower LME sensitivity S LME >-15 kJ / mol. LME

[0105] Test analysis:

[0106] ​Under the condition of resistance spot welding process, corresponding spot welding joints are obtained, the resistance spot welding sample is cut by a wire cutting machine, the sample containing all welding feature areas of the spot welding joint is cut off, the cut sample is surface washed to prevent foreign matter from interfering with the test result, and the washed sample is dried; the dried sample is ground and polished, the sample is photographed under a metallographic microscope after being ground and polished, and a morphology picture of the ground and polished surface is obtained, as shown in Figure 4 ; wherein, Figure 4 (a), (b), (d) and (e) are LME cracks of the shoulder of the spot of the IF steel resistance spot welding joint, Figure 4 (c) is the macroscopic metallograph of the spot of the IF steel resistance spot welding joint.

[0107] For the metallographic measurement of the LME crack length, the maximum crack length observed is 35 μm, which is lower than 10% of the plate thickness 1.4 mm, and meets the standard requirement.

[0108] The above embodiments of the present application relate to the technical field of high-strength steel for automobiles, and adopt an advanced high-strength steel composition system design criterion with low LME (Liquid metal embrittlement) sensitivity. The present application determines the boundary value of the LME sensitivity of the advanced high-strength steel that meets the actual requirement in combination with factors such as chemical composition, mixing enthalpy, solute distribution coefficient and the like, and S LME <-17 kJ / mol corresponds to a steel composition with a serious LME tendency, -17 kJ / mol < S LME <-15 kJ / mol corresponds to a steel composition with a higher LME tendency, S LME >-15 kJ / mol corresponds to a steel composition with a smaller LME tendency. Based on the formula of the LME sensitivity index, the advanced high-strength steel with low LME sensitivity is guided and designed.

[0109] Example Five:

[0110] The present embodiment is basically the same as the foregoing embodiments, and the particularity lies in that:

[0111] In the present embodiment, a high-strength steel composition design and analysis system with low liquid metal embrittlement sensitivity executes the program of the high-strength steel composition design and analysis method with low liquid metal embrittlement sensitivity described in the foregoing embodiments, and includes an input module, a data analysis processing module, an output module and a storage module.

[0112] The input module is used to input the composition content information of different high-strength steels to be analyzed, the mixing enthalpy of the high-strength steel base element and the zinc element, and the solute distribution coefficient data information of part of the elements in the high-strength steel base.

[0113] The data analysis processing module executes the computer program of the high-strength steel composition design and analysis method with low liquid metal embrittlement sensitivity.

[0114] The output module outputs the design analysis results of high-strength steel with low sensitivity to liquid metal embrittlement.

[0115] The storage module is used to store data from computer programs and computational analysis processes.

[0116] The embodiments of this invention adopt the design criteria for advanced high-strength steel composition systems with low LME (Liquid metal embrittlement) sensitivity. Combining factors such as chemical composition, enthalpy of mixing, and solute partition coefficient, an advanced high-strength steel LME sensitivity index S is defined and proposed. LME Based on the formula for the LME sensitivity index, an advanced high-strength steel with low LME sensitivity was designed and applied to the testing, analysis, and evaluation of high-strength steel systems prone to LME formation. The more negative the value calculated in the above embodiments, the higher the LME sensitivity of the corresponding steel grade, i.e., the more prone it is to LME cracking. By statistically calculating the LME sensitivity index of advanced galvanized high-strength steels with different compositions, the above embodiments can obtain the boundary value, S, for the advanced high-strength steel to meet practical requirements for LME sensitivity. LME The value <-17 kJ / mol corresponds to a steel composition with a severe LME tendency. LME The steel composition with a lower than -15 kJ / mol concentration corresponds to a higher LME tendency. LME A concentration >-15 kJ / mol corresponds to steel compositions with a lower LME (Liquid Metal Embrittlement) tendency. This invention, based on the LME sensitivity index formula, guides and designs advanced high-strength steels with low LME sensitivity. The high-strength steel composition design and analysis system of this invention, with its low liquid metal embrittlement sensitivity, can perform rapid calculations and predictions via computer programs, enabling quick and accurate assessment of whether the composition of advanced high-strength steel meets standards, and conducting composition design analysis for high-strength steels with low liquid metal embrittlement sensitivity.

[0117] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Various changes can be made according to the purpose of the invention. Any changes, modifications, substitutions, combinations or simplifications made based on the spirit and principle of the technical solution of the present invention shall be equivalent substitutions. As long as they meet the purpose of the invention and do not deviate from the technical principle and inventive concept of the present invention, they shall fall within the protection scope of the present invention.​

Claims

1. A method for designing and analyzing the composition of high-strength steel with low sensitivity to liquid metal embrittlement, characterized in that: The design criteria for using a galvanized high-strength steel composition system are as follows: Based on existing data on the chemical composition of high-strength steel matrix, the enthalpy of mixture of high-strength steel matrix elements and zinc, and the solute partition coefficients of some elements in the high-strength steel matrix, a susceptibility index S for liquid metal embrittlement (LME) of high-strength steel is defined and proposed. LME Based on the formula for calculating the liquid metal embrittlement (LME) sensitivity index, the LME sensitivity index of high-strength steel with different compositions is statistically calculated. The boundary value of the LME sensitivity of high-strength steel to meet the actual requirements is obtained, thereby obtaining the composition of high-strength steel that meets the low LME sensitivity standard, which is used for the composition design of galvanized high-strength steel with low LME sensitivity. The formula for the liquid metal embrittlement (LME) sensitivity index is as follows: S LME =∑w i ×M i ×(1-k i ); Where i is an element, w i For the mass percentage of the i-th element, the value is the actual content percentage multiplied by 100, M i The enthalpy of mixture of element i and Zn is expressed in kJ / mol. i Let be the solute partition coefficient of the i-th element in the iron matrix, 0 <k i <1; Based on the formula for calculating the liquid metal embrittlement (LME) susceptibility index, the following analytical method was used to statistically analyze and calculate the LME susceptibility index of high-strength steels with different compositions: Based on the formula for calculating the liquid metal embrittlement (LME) sensitivity index, the LME sensitivity index S of high-strength steels with different compositions is analyzed. LME Calculations were performed to obtain the results for high-strength steels with different compositions, and then the results were compared: (1) When S LME When the value is less than -17 kJ / mol, the corresponding high-strength steel has a steel composition with a severe LME tendency. (2) When -17kJ / mol LME When the value is less than -15 kJ / mol, the corresponding high-strength steel has a steel composition with a higher tendency for LME (Limited Metal Equilibrium).​ (3) When S LME When the value is >-15 kJ / mol, the corresponding high-strength steel has a steel composition with a smaller tendency for LME. Based on the results obtained in (3), the standard requirements for high-strength steel composition that meets the low embrittlement sensitivity of liquid metal were determined.

2. The method for designing and analyzing the composition of high-strength steel with low embrittlement sensitivity to liquid metals according to claim 1, characterized in that: The high-strength steels include quenching and partitioning steels, twinning induced plasticity steels, dual-phase steels, and other high-strength steel systems that exhibit a tendency to produce LME (Limited Metal Equilibrium).

3. The method for designing and analyzing the composition of high-strength steel with low embrittlement sensitivity to liquid metals according to claim 1, characterized in that: High-strength steel is composed of at least one element that can exist in steel, including C, Si, Mn, and Al.

4. The method for designing and analyzing the composition of high-strength steel with low embrittlement sensitivity to liquid metals according to claim 1, characterized in that: The composition range of high-strength steel, calculated as a percentage by mass, is as follows: C≤0.12%; Si≤0.5%; Mn: 0.3-2.7%; Mo≤0.5%; Al≤0.015%; Nb≤0.035%; Ti≤0.03%; P≤0.015％； S≤0.001%; ​​the remainder is Fe and unavoidable impurities.

5. The method for designing and analyzing the composition of high-strength steel with low embrittlement sensitivity in liquid metals according to claim 1, characterized in that: The calculated LME embrittlement sensitivity index S of high-strength steel is... LME The value of S obtained through calculation LME The more negative the value, the higher the sensitivity of the high-strength steel to liquid metal embrittlement (LME), meaning it is more prone to producing LME cracks.

6. The method for designing and analyzing the composition of high-strength steel with low embrittlement sensitivity to liquid metals according to claim 1, characterized in that: For high-strength steel plates, the length of the liquid metal embrittlement (LME) crack in high-strength steel that meets the low liquid metal embrittlement sensitivity standard shall not exceed 10% of the thickness of the high-strength steel plate.

7. The method for compositional design and analysis of high-strength steel with low embrittlement sensitivity to liquid metals according to claim 6, characterized in that: For high-strength steel that meets the low liquid metal embrittlement sensitivity standard, the length of the liquid metal embrittlement (LME) crack is no greater than 4.1% of the thickness of the high-strength steel plate.

8. A high-strength steel composition design and analysis system with low susceptibility to liquid metal embrittlement, executing the program of the high-strength steel composition design and analysis method with low susceptibility to liquid metal embrittlement as described in claim 1, characterized in that: It includes an input module, a data analysis and processing module, an output module, and a storage module; The input module is used to input information on the composition content of different high-strength steels to be analyzed, the enthalpy of mixing of the matrix elements and zinc elements of the high-strength steel, and the solute partition coefficient data of some elements in the high-strength steel matrix. The data analysis and processing module executes a computer program for designing and analyzing the composition of high-strength steel with low sensitivity to liquid metal embrittlement. The output module outputs the design analysis results of high-strength steel with low sensitivity to liquid metal embrittlement. The storage module is used to store data from computer programs and computational analysis processes.

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