Method and device for describing yield behavior, product and electronic equipment

Abstract

The invention provides a method and device for describing a yield behavior, a product and electronic equipment, and relates to the technical field of metal material mechanical property characterization. The isotropic yield criterion comprises a first parameter and a second parameter which are used for adjusting the symmetry of the third invariant of the deviatoric stress tensor, and a third parameter used for adjusting the asymmetry of the third invariant of the deviatoric stress tensor; the corresponding relation between the first parameter and the second parameter and the value range of the third parameter can be determined through a Hesse matrix and a yield surface curvature algorithm, and the isotropic yield criterion after parameter determination is converted into the anisotropic yield criterion, so that the strength difference effect and the anisotropic behavior of the material can be predicted. In this way, when the metal material is applied to the multi-load working condition and the complex stress state, the yield behavior of the metal material in the complex stress state can be represented with high precision.

Description

Technical Field

[0001] The present application relates to the technical field of characterization of mechanical properties of metal materials, and in particular to a method for describing yield behavior, a device for describing yield behavior, a computer program product, and an electronic device. Background Art

[0002] Metal materials are widely used in aerospace, shipbuilding, automobile, construction and other fields due to their mechanical properties. Generally speaking, metal materials can be classified according to their crystal structure into: face centered cubic (FCC), body centered cubic (BCC) and hexagonal closed packed (HCP).

[0003] The plastic properties of metal materials are usually affected by loading conditions (such as loading direction, stress state, etc.), which leads to complex yield behaviors of metal materials (such as SD effect, anisotropy, etc.)

[0004] In order to obtain accurate results, it is necessary to accurately describe the yield behavior of metal materials. In the related art, the way to describe the yield behavior of metal materials is to use yield criteria (such as Von Mises, Tresca, etc.), which can be used to describe the isotropic behavior of metal materials, but cannot predict the strength difference effect and anisotropic behavior of metal materials.

[0005] Based on this, when metal materials are used in processes with multiple load conditions and complex stress states (such as sheet metal forming processes, typical aircraft joint service processes, etc.), related technologies cannot accurately characterize the yield behavior of metal materials under complex stress states. Therefore, how to accurately predict the strength difference effect and anisotropic behavior of metal materials has become an urgent problem to be solved.

[0006] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present application, and therefore may include information that does not constitute an existing solution known to ordinary technicians in the field. Summary of the invention

[0007] The purpose of the present application is to provide a method for describing yield behavior, an apparatus for describing yield behavior, a computer-readable storage medium and an electronic device, which can construct an original isotropic yield criterion based on stress invariants, and the isotropic yield criterion includes a first parameter and a second parameter for adjusting the symmetry of the third invariant of the deviator stress tensor, and a third parameter for adjusting the asymmetry of the third invariant of the deviator stress tensor. Then, the Hessian matrix and the yield surface curvature algorithm can be used to determine the correspondence between the first parameter and the second parameter and the value range of the third parameter, and the isotropic yield criterion after determining the parameters can be transformed into an anisotropic yield criterion to predict the material strength difference effect and anisotropic behavior. In this way, when the metal material is applied to multiple load conditions and complex stress states, the yield behavior of the metal material under complex stress states can be characterized with high precision.

[0008] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by the practice of the present application.

[0009] According to one aspect of the present application, a method for describing yield behavior is provided, the method comprising:

[0010] An isotropic yield criterion is constructed based on the stress invariant; wherein the isotropic yield criterion includes a first parameter and a second parameter for adjusting the symmetry of the third invariant of the deviator stress tensor, and a third parameter for adjusting the asymmetry of the third invariant of the deviator stress tensor;

[0011] Based on the Hessian matrix and yield surface curvature algorithm, the corresponding relationship between the first parameter and the second parameter and the value range of the third parameter are determined, and the corresponding relationship and the value range are applied to the isotropic yield criterion;

[0012] The isotropic yield criterion is transformed into an anisotropic yield criterion based on the generalized stress invariant for the stress tensor;

[0013] Predict the effects of material strength differences and anisotropic behavior based on anisotropic yield criteria.

[0014] In an exemplary embodiment of the present application, it further includes:

[0015] According to the viscoplastic self-consistent polycrystal plasticity model, the first yield point data of face-centered cubic, the second yield point data of body-centered cubic, and the third yield point data of hexagonal close-packed are generated;

[0016] Based on the isotropic yield criterion, a first data curve of face-centered cubic, a second data curve of body-centered cubic, and a third data curve of hexagonal close-packed are generated;

[0017] The accuracy of the isotropic yield criterion is determined based on the coincidence degree between the first yield point data and the first data curve, the coincidence degree between the second yield point data and the second data curve, and the coincidence degree between the third yield point data and the third data curve.

[0018] In an exemplary embodiment of the present application, it further includes:

[0019] According to the numerical simulation model based on crystal plasticity theory, the fourth yield point data of the in-plane compression process of zirconium bell rolled plate under different pre-strains and the fifth yield point data of the thickness compression process of zirconium bell rolled plate under different pre-strains are generated;

[0020] Based on the anisotropic yield criterion, a fourth data curve of the in-plane compression process of the zirconium bell rolled plate under different pre-strains and a fifth data curve of the thickness compression process of the zirconium bell rolled plate under different pre-strains are generated;

[0021] The accuracy of the anisotropic yield criterion is determined based on the degree of coincidence between the fourth yield point data and the fourth data curve, and the degree of coincidence between the fifth yield point data and the fifth data curve.

[0022] In an exemplary embodiment of the present application, it further includes:

[0023] Stress components representing the anisotropic yield criterion in uniaxial tension tests, uniaxial compression tests, equibiaxial tension tests, and equibiaxial compression tests;

[0024] Based on the anisotropic yield criterion and each stress component, a yield stress model for each stress state is proposed; among them, the uniaxial tensile yield stress model is used to characterize the relationship between the anisotropic yield criterion and the sampling angle.

[0025] In an exemplary embodiment of the present application, it further includes:

[0026] Generate plastic strain ratio coefficient for anisotropic yield criterion;

[0027] The accuracy of the anisotropic yield criterion is verified based on the plastic strain ratio coefficient.

[0028] In an exemplary embodiment of the present application, it further includes:

[0029] Based on the plastic strain ratio coefficient and anisotropic yield criterion, the error function between the prediction results and the test results is constructed;

[0030] Minimize the value of the error function based on the descent simplex method to identify the anisotropic material constants in the anisotropic yield criterion.

[0031] In an exemplary embodiment of the present application, the isotropic yield criterion is expressed as:

[0032]

[0033] Among them, I1 is the first invariant of the stress tensor, J2 is the second invariant of the deviator stress tensor, J3 is the third invariant of the deviator stress tensor, σ1, σ2, σ3 represent the three principal stresses, S1, S2, S3 represent the three principal deviator stresses, σ Y is the yield stress obtained by uniaxial tension, a and n are the first and second parameters for adjusting the symmetry of J3, b is the third parameter for adjusting the asymmetry of J3, μ is the parameter for adjusting the hydrostatic pressure sensitivity, and k is derived based on the uniaxial condition, which is expressed as:

[0034] According to one aspect of the present application, a device for describing yield behavior is provided, comprising:

[0035] An isotropic yield criterion construction unit is used to construct an isotropic yield criterion based on a stress invariant; wherein the isotropic yield criterion includes a first parameter and a second parameter for adjusting the symmetry of the third invariant of the deviator stress tensor, and a third parameter for adjusting the asymmetry of the third invariant of the deviator stress tensor;

[0036] A parameter determination unit, used for determining the corresponding relationship between the first parameter and the second parameter and the value range of the third parameter based on the Hessian matrix and the yield surface curvature algorithm, and applying the corresponding relationship and the value range to the isotropic yield criterion;

[0037] Anisotropic yield criterion determination unit, used to transform the isotropic yield criterion into anisotropic yield criterion based on the generalized stress invariant for the stress tensor;

[0038] Prediction unit for predicting material strength difference effects and anisotropic behavior based on anisotropic yield criteria.

[0039] In an exemplary embodiment of the present application, it further includes:

[0040] A yield point data determination unit is used to generate the first yield point data of face-centered cubic, the second yield point data of body-centered cubic, and the third yield point data of hexagonal close-packed according to the viscoplastic self-consistent polycrystalline plasticity model;

[0041] A data curve determination unit, for generating a first data curve of face-centered cubic, a second data curve of body-centered cubic, and a third data curve of hexagonal close-packed based on an isotropic yield criterion;

[0042] The accuracy determination unit is used to determine the accuracy of the isotropic yield criterion based on the coincidence degree between the first yield point data and the first data curve, the coincidence degree between the second yield point data and the second data curve, and the coincidence degree between the third yield point data and the third data curve.

[0043] In an exemplary embodiment of the present application, wherein:

[0044] The yield point data determination unit is also used to generate the fourth yield point data of the in-plane compression process of the zirconium bell rolled plate under different pre-strains and the fifth yield point data of the thickness compression process of the zirconium bell rolled plate under different pre-strains according to the numerical simulation model based on the crystal plasticity theory;

[0045] The data curve determination unit is also used to generate a fourth data curve of the in-plane compression process of the zirconium bell rolled plate under different pre-strains and a fifth data curve of the thickness compression process of the zirconium bell rolled plate under different pre-strains based on the anisotropic yield criterion;

[0046] The accuracy determination unit is further used to determine the accuracy of the anisotropic yield criterion based on the coincidence degree between the fourth yield point data and the fourth data curve, and the coincidence degree between the fifth yield point data and the fifth data curve.

[0047] In an exemplary embodiment of the present application, it further includes:

[0048] Stress component determination unit, used to represent the stress components of the anisotropic yield criterion in uniaxial tension test, uniaxial compression test, equibiaxial tension test, equibiaxial compression test;

[0049] The uniaxial tensile yield stress model determination unit is used for yield stress models of various stress states based on anisotropic yield criterion and various stress components; wherein the uniaxial tensile yield stress model is used to characterize the relationship between the anisotropic yield criterion and the sampling angle.

[0050] In an exemplary embodiment of the present application, it further includes:

[0051] Plastic strain ratio coefficient generation unit, used to generate plastic strain ratio coefficient of anisotropic yield criterion;

[0052] An accuracy verification unit is used to verify the accuracy of the anisotropic yield criterion based on the plastic strain ratio coefficient.

[0053] In an exemplary embodiment of the present application, it further includes:

[0054] An error function determination unit is used to construct an error function of prediction results and test results based on the plastic strain ratio coefficient and the anisotropic yield criterion;

[0055] A constant identification unit is used to identify the anisotropic material constants in anisotropic yield criterion by minimizing the value of the error function based on the descent simplex method.

[0056] In an exemplary embodiment of the present application, the isotropic yield criterion is expressed as:

[0057]

[0058] Among them, I1 is the first invariant of the stress tensor, J2 is the second invariant of the deviator stress tensor, J3 is the third invariant of the deviator stress tensor, σ1, σ2, σ3 represent the three principal stresses, S1, S2, S3 represent the three principal deviator stresses, σ Y is the yield stress obtained by uniaxial tension, a and n are the first and second parameters for adjusting the symmetry of J3, b is the third parameter for adjusting the asymmetry of J3, μ is the parameter for adjusting the hydrostatic pressure sensitivity, and k is derived based on the uniaxial condition, which is expressed as:

[0059] According to one aspect of the present application, a computer program product is provided, including a computer program, and when the computer program is executed by a processor, any one of the above methods is implemented.

[0060] According to one aspect of the present application, an electronic device is provided, comprising: a processor; and a memory for storing executable instructions of the processor; wherein the processor is configured to perform any one of the above methods by executing the executable instructions.

[0061] The exemplary embodiments of the present application may have some or all of the following beneficial effects:

[0062] In a method for describing yield behavior provided in an example embodiment of the present application, an original isotropic yield criterion can be constructed based on stress invariants. The isotropic yield criterion includes a first parameter and a second parameter for adjusting the symmetry of the third invariant of the deviatoric stress tensor, and a third parameter for adjusting the asymmetry of the third invariant of the deviatoric stress tensor. Then, the Hessian matrix and the yield surface curvature algorithm can be used to determine the correspondence between the first parameter and the second parameter and the value range of the third parameter. The isotropic yield criterion after determining the parameters can be transformed into an anisotropic yield criterion to predict the material strength difference effect and anisotropic behavior. In this way, when the metal material is applied to multiple load conditions and complex stress states, the yield behavior of the metal material under complex stress states can be characterized with high precision.

[0063] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] The drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0065] Figure 1 A flowchart of a method for describing yielding behavior according to an embodiment of the present application is schematically shown;

[0066] Figure 2 A schematic diagram schematically shows a corresponding relationship between a first parameter and a second parameter according to an embodiment of the present application;

[0067] Figure 3 A schematic diagram schematically shows the relationship between the parameter μ and the yield criterion shape according to an embodiment of the present application;

[0068] Figure 4 A schematic diagram schematically shows the relationship between the third parameter b and the yield criterion shape according to an embodiment of the present application;

[0069] Figure 5 A schematic diagram schematically shows the relationship between the first parameter a and the yield criterion shape according to an embodiment of the present application;

[0070] Figure 6 A schematic diagram of prediction results based on a viscoplastic self-consistent polycrystalline plasticity model and an isotropic yield criterion according to an embodiment of the present application is schematically shown;

[0071] Figure 7 A schematic diagram of the fourth yield point data of the zirconium bell rolled plate in the in-plane compression process under different pre-strains according to an embodiment of the present application is schematically shown;

[0072] Figure 8 Schematically showing the fifth yield point data of the zirconium bell rolled plate thickness compression process under different pre-strains according to one embodiment of the present application;

[0073] Fig. 9 A schematic diagram showing the prediction results of the tensile yield stress of AA2008-T4 aluminum alloy at different direction angles according to the anisotropic yield criterion of one embodiment of the present application is shown;

[0074] Fig.10 A schematic diagram showing the prediction results of the compressive yield stress of AA2008-T4 aluminum alloy at different direction angles according to the anisotropic yield criterion of one embodiment of the present application is shown;

[0075] Fig.11 A schematic diagram showing the prediction results of the Lankford coefficient of AA2008-T4 aluminum alloy at different direction angles according to the anisotropic yield criterion of one embodiment of the present application is shown;

[0076] Fig.12A schematic diagram showing the prediction results of the yield surface of AA2008-T4 aluminum alloy according to the anisotropic yield criterion of one embodiment of the present application is shown;

[0077] Fig.13 A structural block diagram of a device for describing yielding behavior according to an embodiment of the present application is schematically shown;

[0078] Fig.14 The structure diagram of a computer system suitable for implementing an electronic device of an embodiment of the present application is schematically shown. DETAILED DESCRIPTION

[0079] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as being limited to the examples set forth herein; on the contrary, these embodiments are provided so that the present application will be more comprehensive and complete, and the concept of the example embodiments will be fully conveyed to those skilled in the art. The described features, structures, or characteristics may be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present application. However, those skilled in the art will appreciate that the technical solutions of the present application may be practiced while omitting one or more of the specific details, or other methods, components, devices, steps, etc. may be adopted. In other cases, known technical solutions are not shown or described in detail to avoid obscuring various aspects of the present application.

[0080] In addition, the accompanying drawings are only schematic illustrations of the present application and are not necessarily drawn to scale. The same reference numerals in the figures represent the same or similar parts, and thus their repeated description will be omitted. Some of the block diagrams shown in the accompanying drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in software form, or implemented in one or more hardware modules or integrated circuits, or implemented in different networks and / or processor devices and / or microcontroller devices.

[0081] See also Figure 1 , Figure 1 A flow chart of a method for describing yield behavior according to an embodiment of the present application is schematically shown. Figure 1 As shown, the method for describing yield behavior may include: steps S110 to S140.

[0082] Step S110: constructing an isotropic yield criterion based on the stress invariant; wherein the isotropic yield criterion includes a first parameter and a second parameter for adjusting the symmetry of the third invariant of the deviator stress tensor, and a third parameter for adjusting the asymmetry of the third invariant of the deviator stress tensor.

[0083] Step S120: determining the corresponding relationship between the first parameter and the second parameter and the value range of the third parameter based on the Hessian matrix and the yield surface curvature algorithm, and applying the corresponding relationship and the value range to the isotropic yield criterion.

[0084] Step S130: transforming the isotropic yield criterion into the anisotropic yield criterion based on the generalized stress invariant for the stress tensor.

[0085] Step S140: predicting material strength difference effect and anisotropic behavior based on the anisotropic yield criterion.

[0086] Implementation Figure 1 The method shown can construct an original isotropic yield criterion based on stress invariants. The isotropic yield criterion includes a first parameter and a second parameter for adjusting the symmetry of the third invariant of the deviatoric stress tensor, and a third parameter for adjusting the asymmetry of the third invariant of the deviatoric stress tensor. Then, the Hessian matrix and the yield surface curvature algorithm can be used to determine the correspondence between the first parameter and the second parameter and the value range of the third parameter. The isotropic yield criterion after determining the parameters can be transformed into an anisotropic yield criterion to predict the material strength difference effect and anisotropic behavior. In this way, when the metal material is applied to multiple load conditions and complex stress states, the yield behavior of the metal material under complex stress states can be characterized with high precision.

[0087] Next, the above steps of this exemplary embodiment are described in more detail.

[0088] In step S110, an isotropic yield criterion is constructed based on the stress invariant; wherein the isotropic yield criterion includes a first parameter and a second parameter for adjusting the symmetry of the third invariant of the deviator stress tensor, and a third parameter for adjusting the asymmetry of the third invariant of the deviator stress tensor.

[0089] Among them, the yield criterion refers to the fact that under certain deformation conditions (such as deformation temperature, deformation speed, etc.), only when the stress components meet a certain relationship, the particle begins to enter the plastic state. This relationship is the yield criterion. The yield criterion is usually expressed as a yield surface or yield position. It is an assumption about the elastic limit under any stress combination.

[0090] Among them, isotropy refers to the property that the physical, chemical and other properties of an object will not change with different directions, that is, the performance values ​​of an object measured in different directions are exactly the same, also known as homogeneity. The property that physical properties do not change with the measurement direction. That is, the properties measured along different directions of the object show the same value. The isotropic yield criterion can be applied to isotropic scenarios. However, when metals are subjected to large plastic deformations, the grain size and orientation change in the deformation direction. As a result, the plastic yield behavior of the material shows direction dependence. In this case, the anisotropic yield criterion is applicable.

[0091] Among them, the stress invariant can be expressed as I1-J2-J3. Specifically, the yield criterion can be established based on the I1-J2-J3 stress invariant framework:

[0092] Among them, I1 is the first invariant of the stress tensor, J2 is the second invariant of the deviator stress tensor, and J3 is the third invariant of the deviator stress tensor; I1 = σ1 + σ2 + σ3, J3=S1S2S3; among them, σ1, σ2, σ3 represent the three principal stresses respectively, and S1, S2, S3 represent the three principal deviatoric stresses respectively.

[0093] Among them, σ Y is the yield stress obtained under uniaxial tension, a and n are parameters for adjusting the symmetry of J3, b is a parameter for adjusting the asymmetry of J3, and μ is a parameter for adjusting the sensitivity to hydrostatic pressure. In addition, k is derived based on the uniaxial condition, which is expressed as: It can be seen that the isotropic form of the yield criterion proposed in this application takes into account the hydrostatic pressure sensitivity and introduces the asymmetry of the third invariant of the stress deviator tensor to simulate the strength difference (SD) effect of pressure-insensitive materials.

[0094] In step S120, the corresponding relationship between the first parameter and the second parameter and the value range of the third parameter are determined based on the Hessian matrix and the yield surface curvature algorithm, and the corresponding relationship and the value range are applied to the isotropic yield criterion.

[0095] Specifically, the Hessian Matrix, also known as the Hessian Matrix, the Hessian Matrix, the Hessian Matrix, etc., is a square matrix composed of the second-order partial derivatives of a multivariate function, which describes the local curvature of the function and is often used in Newton's method to solve optimization problems. The Hessian Matrix can be used to determine the extreme value of a multivariate function. In the optimization design of practical engineering problems, the listed objective functions are often very complex. In order to simplify the problem, the objective function is often expanded into a Taylor polynomial in the neighborhood of a certain point to approximate the original function. At this time, the Hessian matrix will be involved in the matrix form of the Taylor expansion of the function at a certain point.

[0096] Specifically, the convexity condition of the isotropic yield criterion can be derived based on the Hessian matrix and the yield surface curvature algorithm. The convexity condition includes the corresponding relationship between the first parameter and the second parameter and the value range of the third parameter. Among them, when the isotropic criterion yield surface satisfies the convexity condition, the corresponding relationship between the first parameter and the second parameter can be expressed as Figure 2 ,exist Figure 2 In the equation, the second parameter n is expressed as an exponential factor n, and its value range can be expressed as:

[0097] Among them, in order to ensure the uniqueness of the solution in the numerical simulation, the yield criterion should be convex. The process of deriving the convexity condition of the yield criterion is as follows:

[0098] The parameter μ in the expression of the yield criterion disclosed in this application does not affect the convexity of the yield criterion. The relationship between the parameter μ and the shape of the yield criterion can be found in Figure 3 In addition, the relationship between the third parameter b and the yield criterion shape can be found in Figure 4 The relationship between the first parameter a and the yield criterion shape can be found in Figure 5 .

[0099] When b = 0, the isotropic yield function of the even function can be obtained: It can be seen that if the two-dimensional cross section is expressed as convex in the π plane, then the three-dimensional yield surface satisfies the convexity. Among them, the π plane can be expressed by a polar coordinate system, in which the effective stress is the radial coordinate and the circumferential coordinate is the stress Lode angle θ, which can be specifically expressed as: where stress Lode angle is a variable that represents the deviatoric stress component in the π plane.

[0100] In addition, the curvature of the yield criterion is expressed as:

[0101] when When , the convexity requirement of the yield criterion is satisfied.

[0102] Since the yield criterion is an even function, the yield condition is the same between uniaxial tension and uniaxial compression. When the π plane satisfies convexity within the stress state range, the yield criterion is convex.

[0103] When a = 0, the isotropic yield criterion containing the odd form of the third invariant of the stress deviator tensor can be obtained: Furthermore, the convexity condition can be calculated based on the Hessian matrix; where the Hessian matrix is ​​expressed as In H, each In order to ensure the convexity of Λ, the Hessian matrix H of Λ is a semi-positive definite matrix.

[0104] The derivation process of the Hessian matrix being a semi-positive definite matrix is:

[0105]

[0106]

[0107] Among them, O ij for The second-order partial derivative, B ij is the second-order partial derivative of J3 / J2.

[0108] Then we can use the method of major and minor determinants to determine the limit of b.

[0109] Based on the above formula, it can be expressed that: Among them, for any i=1,2,3, when hour, Therefore the determinant of the Hessian matrix is ​​equal to 0.

[0112] The second-order major and minor determinants of the Hessian matrix are:

[0113] Based on this, we can know that if H 11 ≥0, then the Hessian matrix is ​​positive semidefinite.

[0115] And, because In is negative, so we only need to ensure This expression satisfies g≥0 within a specific range. Then, we can set g(ξ)≥0 to calculate the specific range That is, the value range of b.

[0116] As an optional embodiment, it also includes:

[0117] According to the viscoplastic self-consistent polycrystal plasticity model, the first yield point data of face-centered cubic, the second yield point data of body-centered cubic, and the third yield point data of hexagonal close-packed are generated;

[0118] Based on the isotropic yield criterion, a first data curve of face-centered cubic, a second data curve of body-centered cubic, and a third data curve of hexagonal close-packed are generated;

[0119] The accuracy of the isotropic yield criterion is determined based on the coincidence degree between the first yield point data and the first data curve, the coincidence degree between the second yield point data and the second data curve, and the coincidence degree between the third yield point data and the third data curve.

[0120] It can be seen that by implementing this optional embodiment, the precision of the isotropic yield criterion can be calculated to clarify the accuracy of the isotropic yield criterion.

[0121] For details, please refer to Figure 6 , based on the viscoplastic self-consistent polycrystal plasticity model (VPSC), the first yield point data of face-centered cubic (FCC) are generated (in Figure 6 VPSC data for BCC), body-centered cubic (BCC) second yield point data (in Figure 6 VPSC data for FCC), the third yield point data of hexagonal close-packed (HCP) (in Figure 6 In it, it is represented as VPSC data for FCP); wherein, the number of the first yield point data, the second yield point data, and the third yield point data are all multiple. Then, based on the isotropic yield criterion, the first data curve of face-centered cubic (the present invention predicts BCC), the second data curve of body-centered cubic (the present invention predicts FCC), and the third data curve of close-packed hexagonal (the present invention predicts FCP) can be generated. Among them, VPSC is a numerical simulation tool based on the theory of crystal plasticity, which is mainly used to predict and simulate the macroscopic plastic deformation behavior and microstructural evolution process of polycrystalline metal materials under complex strain conditions.

[0122] Furthermore, the accuracy of the isotropic yield criterion can be determined based on the degree of overlap between the first yield point data and the first data curve, the degree of overlap between the second yield point data and the second data curve, and the degree of overlap between the third yield point data and the third data curve; wherein, the higher the degree of overlap, the higher the accuracy of the final calculation.

[0123] In addition, the isotropic yield criterion can also be parameterized based on the accuracy of the isotropic yield criterion to improve the accuracy of the isotropic yield criterion.

[0124] In step S130, the isotropic yield criterion is transformed into an anisotropic yield criterion based on the generalized stress invariant for the stress tensor.

[0125] Specifically, the isotropic yield criterion can be transformed based on the generalized stress invariant to the stress tensor to obtain the orthogonal anisotropic yield criterion: Among them, σ Yis the yield stress obtained by uniaxial tension in the rolling direction, J′2 is the generalized expression of the second invariant of the deviator stress tensor, and J″3 is the generalized expression of the third invariant of the deviator stress tensor. is the anisotropic expression of the first invariant of the stress tensor.

[0126] in, Specifically, a i is the anisotropy parameter of the second invariant of the generalized deviatoric stress tensor, i=1,2,3,4,5,6.

[0127] in, Specifically, b i is the third invariant anisotropy parameter of the generalized deviatoric stress tensor, i = 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11.

[0129] in, Specifically, h x 、h y 、h z is the anisotropy parameter of the hydrostatic pressure.

[0130] As an optional embodiment, it also includes:

[0131] According to the numerical simulation model based on crystal plasticity theory, the fourth yield point data of the in-plane compression process of zirconium bell rolled plate under different pre-strains are generated (see Figure 7 , Figure 7 Each closed curve represents a different pre-strain), the fifth yield point data of the zirconium bell rolled plate thickness compression process under different pre-strains (see Figure 8 , Figure 8 Each closed curve in represents a different pre-strain);

[0132] Based on the anisotropic yield criterion, a fourth data curve of the in-plane compression process of the zirconium bell rolled plate under different pre-strains and a fifth data curve of the thickness compression process of the zirconium bell rolled plate under different pre-strains are generated;

[0133] The accuracy of the anisotropic yield criterion is determined based on the degree of coincidence between the fourth yield point data and the fourth data curve, and the degree of coincidence between the fifth yield point data and the fifth data curve.

[0134] It can be seen that by implementing this optional embodiment, the precision of the anisotropic yield criterion can be calculated to clarify the accuracy of the anisotropic yield criterion.

[0135] Specifically, the anisotropic yield criterion can be parameter-adjusted based on the accuracy of the anisotropic yield criterion to improve the accuracy of the anisotropic yield criterion. When the fourth yield point data completely hits the fourth data curve, and the fifth yield point data completely hits the fifth data curve, it can be determined that the anisotropic yield criterion has high accuracy and robustness.

[0136] As an optional embodiment, it also includes:

[0137] Stress components representing the anisotropic yield criterion in uniaxial tension tests, uniaxial compression tests, equibiaxial tension tests, and equibiaxial compression tests;

[0138] Based on the anisotropic yield criterion and each stress component, a yield stress model for each stress state is proposed; among them, the uniaxial tensile yield stress model is used to characterize the relationship between the anisotropic yield criterion and the sampling angle.

[0139] It can be seen that by implementing this optional embodiment, a uniaxial tensile yield stress model can be determined based on the anisotropic yield criterion and each stress component, so as to be applied to a uniaxial tensile yield stress scenario.

[0140] Specifically, in uniaxial tension test, uniaxial compression test, equibiaxial tension test, and equibiaxial compression test, the stress component of the anisotropic yield criterion is expressed as: σ xx =T θ (C θ )cos 2 θ,σ yy =T θ (C θ )sin 2 θ,σ xy =T θ (C θ )sinθcosθ,σ xx =σ yy =T b (C b ), where T θ and C θ represent the yield stress under uniaxial tension test and the yield stress under uniaxial compression test, T b and C b represent the yield stress under equibiaxial tension test and the yield stress under equibiaxial compression test, respectively.

[0141] Furthermore, the stress component of the anisotropic yield criterion can be substituted into the expression of the anisotropic yield criterion to obtain the following expression:

[0142] Furthermore, for the xy plane, taking the uniaxial tensile test as an example, the stress component of the anisotropic yield criterion can be substituted into the expression of J′2, the expression of J″3, The expression of , we get the following substitution result:

[0143] Then, substitute the above result into T θ (T b ), we can get the final expression of uniaxial tensile yield stress:

[0144]

[0145] As an optional embodiment, it also includes:

[0146] Generate plastic strain ratio coefficient for anisotropic yield criterion;

[0147] The accuracy of the anisotropic yield criterion is verified based on the plastic strain ratio coefficient.

[0148] It can be seen that by implementing this optional embodiment, the plastic strain ratio coefficient can be characterized with high precision, which solves the problem that the existing anisotropic yield criterion is difficult to accurately describe the anisotropic yield stress and the plastic strain ratio coefficient at the same time.

[0149] Specifically, the method for calculating the plastic strain ratio (Lankford) coefficient of the anisotropic yield criterion is to first find the partial derivative of the anisotropic yield criterion. The process of finding the partial derivative is as follows:

[0150]

[0151]

[0152] Furthermore, based on the above partial derivative results and the Lankford coefficient calculation method of the anisotropic yield criterion, Verify the accuracy of the anisotropic yield criterion. and is the partial derivative of the yield criterion with respect to the stress component.

[0153] As an optional embodiment, it also includes:

[0154] Based on the plastic strain ratio coefficient and anisotropic yield criterion, the error function between the prediction results and the test results is constructed;

[0155] Minimize the value of the error function based on the descent simplex method to identify the anisotropic material constants in the anisotropic yield criterion.

[0156] It can be seen that by implementing this optional embodiment, the anisotropic material constant in the anisotropic yield criterion can be determined, so as to be better applied to the prediction process for anisotropic materials.

[0157] Specifically, according to the Lankford coefficient and parameters involved in the plastic description of the yield criterion, an error function between the prediction results and the test results is constructed:

[0158]

[0159] Where, l, m, n represent the number of test yield stresses and Lankford coefficients at different direction angles θ; are the yield stress and Lankford coefficient obtained from the experiment; are the corresponding values ​​predicted according to the proposed yield criterion; W Tθ , W Tb , W Cθ , W Cb , W rθ , W rb , are the weight coefficients of tensile and compressive yield stresses and Lankford coefficients, respectively.

[0160] Furthermore, the value of the error function can be minimized through the optimization algorithm of the down-hill simplex method to identify the anisotropic material constants in the proposed yield function.

[0161] Among them, the basic idea of ​​the simplex method is to construct a non-degenerate initial simplex in multidimensional space, perform a series of geometric operations, such as reflection, expansion, contraction, etc., and gradually move the simplex to the extreme point.

[0162] In step S140 , the material strength difference effect and anisotropic behavior are predicted based on the anisotropic yield criterion.

[0163] Specifically, the anisotropic yield criterion constructed based on the present application solves the problem that conventional yield criteria such as Von Mises and Tresca can only describe the symmetric yield surface of the material, but cannot predict the strength difference effect of hydrostatic pressure sensitive materials and hydrostatic pressure insensitive materials, and realizes the simultaneous prediction of material strength difference effect and anisotropic behavior.

[0164] For the application results of the anisotropic yield criterion, please refer to 9~ Fig.12 , Fig. 9 It is the prediction result of the anisotropic yield criterion for the tensile yield stress of AA20082008-T4 aluminum alloy at different direction angles. Fig.10is the prediction result of the anisotropic yield criterion for the compressive yield stress of AA2008-T4 aluminum alloy at different angles. Fig.11 is the prediction result of the anisotropic yield criterion for the Lankford coefficient of AA2008-T4 aluminum alloy at different direction angles. Fig.12 It is the prediction result of the anisotropic yield criterion for the yield surface of AA2008-T4 aluminum alloy.

[0165] See also Fig.13 , Fig.13 The structure block diagram of the device for describing yield behavior according to an embodiment of the present application is schematically shown. Figure 1 The method shown corresponds to Fig.13 As shown, the device 1300 for describing yield behavior includes:

[0166] An isotropic yield criterion construction unit 1301 is used to construct an isotropic yield criterion based on a stress invariant; wherein the isotropic yield criterion includes a first parameter and a second parameter for adjusting the symmetry of the third invariant of the deviator stress tensor, and a third parameter for adjusting the asymmetry of the third invariant of the deviator stress tensor;

[0167] A parameter determination unit 1302 is used to determine the corresponding relationship between the first parameter and the second parameter and the value range of the third parameter based on the Hessian matrix and the yield surface curvature algorithm, and apply the corresponding relationship and the value range to the isotropic yield criterion;

[0168] An anisotropic yield criterion determination unit 1303, used for transforming the isotropic yield criterion into the anisotropic yield criterion based on the generalized stress invariant for the stress tensor;

[0169] The prediction unit 1304 is used to predict the material strength difference effect and anisotropic behavior based on the anisotropic yield criterion.

[0170] The isotropic yield criterion is expressed as:

[0171]

[0172] Among them, I1 is the first invariant of the stress tensor, J2 is the second invariant of the deviator stress tensor, J3 is the third invariant of the deviator stress tensor, σ1, σ2, σ3 represent the three principal stresses, S1, S2, S3 represent the three principal deviator stresses, σ Y is the yield stress obtained by uniaxial tension, a and n are the first and second parameters for adjusting the symmetry of J3, b is the third parameter for adjusting the asymmetry of J3, μ is the parameter for adjusting the hydrostatic pressure sensitivity, and k is derived based on the uniaxial condition, which is expressed as:

[0173] It can be seen that implementation Fig.13 The device shown can construct an original isotropic yield criterion based on stress invariants. The isotropic yield criterion includes a first parameter and a second parameter for adjusting the symmetry of the third invariant of the deviator stress tensor, and a third parameter for adjusting the asymmetry of the third invariant of the deviator stress tensor. Then, the Hessian matrix and yield surface curvature algorithm can be used to determine the correspondence between the first parameter and the second parameter and the value range of the third parameter. The isotropic yield criterion after determining the parameters can be transformed into an anisotropic yield criterion to predict the material strength difference effect and anisotropic behavior. In this way, when the metal material is applied to multiple load conditions and complex stress states, the yield behavior of the metal material under complex stress states can be characterized with high precision.

[0174] In an exemplary embodiment of the present application, it further includes:

[0175] A yield point data determination unit is used to generate the first yield point data of face-centered cubic, the second yield point data of body-centered cubic, and the third yield point data of hexagonal close-packed according to the viscoplastic self-consistent polycrystalline plasticity model;

[0176] A data curve determination unit, for generating a first data curve of face-centered cubic, a second data curve of body-centered cubic, and a third data curve of hexagonal close-packed based on an isotropic yield criterion;

[0177] The accuracy determination unit is used to determine the accuracy of the isotropic yield criterion based on the coincidence degree between the first yield point data and the first data curve, the coincidence degree between the second yield point data and the second data curve, and the coincidence degree between the third yield point data and the third data curve.

[0178] It can be seen that by implementing this optional embodiment, the precision of the isotropic yield criterion can be calculated to clarify the accuracy of the isotropic yield criterion.

[0179] In an exemplary embodiment of the present application, wherein:

[0180] The yield point data determination unit is also used to generate the fourth yield point data of the in-plane compression process of the zirconium bell rolled plate under different pre-strains and the fifth yield point data of the thickness compression process of the zirconium bell rolled plate under different pre-strains according to the numerical simulation model based on the crystal plasticity theory;

[0181] The data curve determination unit is also used to generate a fourth data curve of the in-plane compression process of the zirconium bell rolled plate under different pre-strains and a fifth data curve of the thickness compression process of the zirconium bell rolled plate under different pre-strains based on the anisotropic yield criterion;

[0182] The accuracy determination unit is further used to determine the accuracy of the anisotropic yield criterion based on the coincidence degree between the fourth yield point data and the fourth data curve, and the coincidence degree between the fifth yield point data and the fifth data curve.

[0183] It can be seen that by implementing this optional embodiment, the precision of the anisotropic yield criterion can be calculated to clarify the accuracy of the anisotropic yield criterion.

[0184] In an exemplary embodiment of the present application, it further includes:

[0185] Stress component determination unit, used to represent the stress components of the anisotropic yield criterion in uniaxial tension test, uniaxial compression test, equibiaxial tension test, equibiaxial compression test;

[0186] The uniaxial tensile yield stress model determination unit is used for yield stress models of various stress states based on anisotropic yield criterion and various stress components; wherein the uniaxial tensile yield stress model is used to characterize the relationship between the anisotropic yield criterion and the sampling angle.

[0187] It can be seen that by implementing this optional embodiment, a uniaxial tensile yield stress model can be determined based on the anisotropic yield criterion and each stress component, so as to be applied to a uniaxial tensile yield stress scenario.

[0188] In an exemplary embodiment of the present application, it further includes:

[0189] Plastic strain ratio coefficient generation unit, used to generate plastic strain ratio coefficient of anisotropic yield criterion;

[0190] An accuracy verification unit is used to verify the accuracy of the anisotropic yield criterion based on the plastic strain ratio coefficient.

[0191] It can be seen that by implementing this optional embodiment, the plastic strain ratio coefficient can be characterized with high precision, which solves the problem that the existing anisotropic yield criterion is difficult to accurately describe the anisotropic yield stress and the plastic strain ratio coefficient at the same time.

[0192] In an exemplary embodiment of the present application, it further includes:

[0193] An error function determination unit is used to construct an error function of prediction results and test results based on the plastic strain ratio coefficient and the anisotropic yield criterion;

[0194] A constant identification unit is used to identify the anisotropic material constants in anisotropic yield criterion by minimizing the value of the error function based on the descent simplex method.

[0195] It can be seen that by implementing this optional embodiment, the anisotropic material constant in the anisotropic yield criterion can be determined, so as to be better applied to the prediction process for anisotropic materials.

[0196] It should be noted that, although several modules or units of the equipment for action execution are mentioned in the above detailed description, this division is not mandatory. In fact, according to the embodiments of the present application, the features and functions of two or more modules or units described above can be embodied in one module or unit. On the contrary, the features and functions of one module or unit described above can be further divided into being embodied by multiple modules or units.

[0197] Since the various functional modules of the device for describing yield behavior in the example embodiment of the present application correspond to the steps of the example embodiment of the method for describing yield behavior described above, for details not disclosed in the device embodiment of the present application, please refer to the embodiment of the method for describing yield behavior described above in the present application.

[0198] See also Fig.14 , Fig.14 A schematic diagram of the structure of a computer system suitable for implementing an electronic device of an embodiment of the present application is shown.

[0199] It should be noted that Fig.14 The computer system 1400 of the electronic device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0200] like Fig.14 As shown, the computer system 1400 includes a central processing unit (CPU) 1401, which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 1402 or the program loaded from the storage part 1408 to the random access memory (RAM) 1403. In the RAM 1403, various programs and data required for system operation are also stored. The CPU 1401, the ROM 1402, and the RAM 1403 are connected to each other through a bus 1404. An input / output (I / O) interface 1405 is also connected to the bus 1404.

[0201] The following components are connected to the I / O interface 1405: an input section 1406 including a keyboard, a mouse, etc.; an output section 1407 including a cathode ray tube (CRT), a liquid crystal display (LCD), etc., and a speaker, etc.; a storage section 1408 including a hard disk, etc.; and a communication section 1409 including a network interface card such as a LAN card, a modem, etc. The communication section 1409 performs communication processing via a network such as the Internet. A drive 1410 is also connected to the I / O interface 1405 as needed. A removable medium 1411, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 1410 as needed, so that a computer program read therefrom is installed into the storage section 1408 as needed.

[0202] In particular, according to an embodiment of the present application, the process described with reference to the flowchart above can be implemented as a computer software program. For example, an embodiment of the present application includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program contains program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication section 1409, and / or installed from a removable medium 1411. When the computer program is executed by a central processing unit (CPU) 1401, various functions defined in the method and apparatus of the present application are executed.

[0203] The exemplary embodiments of the present disclosure also provide a computer program product, which includes a computer program, and when the computer program is executed by a processor, the method for describing yielding behavior is implemented.

[0204] In one embodiment, the computer program product may be a tangible product containing a computer program, such as a computer-readable storage medium storing a computer program. The readable storage medium may be a storage medium based on electrical, magnetic, optical, electromagnetic, infrared, or other signals, including but not limited to: random access memory (RAM), read-only memory (ROM), magnetic tape, floppy disk, flash memory (Flash), mechanical hard disk (HDD), solid-state drive (SSD), and the like. Exemplarily, the computer program product may be implemented as a non-volatile storage medium storing a computer program, such as a read-only memory, a NAND flash memory, and the like.

[0205] In one embodiment, the computer program product may be an intangible product including a computer program. Exemplarily, the computer program product may be implemented as a virtual digital product, such as a digital file storing an executable file, an installation package, etc. of the computer program.

[0206] The code of the computer program can be written in one or more programming languages. Programming languages ​​such as C language, Java, C++, etc. The program code can be executed entirely on the user computing device, or partially on the user computing device, or as a separate software package, or partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server. In the case of a remote computing device, the remote computing device can be connected to the user computing device through any type of network, such as a local area network (LAN), a wide area network (WAN), etc., or can be connected to an external computing device (e.g., an Internet connection provided by an operator).

[0207] The computer program can be carried or transmitted by electrical, magnetic, optical, electromagnetic, infrared and other signals. The electronic device can convert the signal carrying the computer program into a digital signal, and then run the computer program. When the computer program is running on the electronic device, its code is used to make the electronic device execute (more specifically, the processor of the electronic device can execute) the method steps of various exemplary embodiments of the present disclosure, such as the method for describing the yield behavior described above, which includes the following steps: constructing an isotropic yield criterion based on stress invariants; wherein the isotropic yield criterion includes a first parameter and a second parameter for adjusting the symmetry of the third invariant of the deviator stress tensor, and a third parameter for adjusting the asymmetry of the third invariant of the deviator stress tensor; determining the corresponding relationship between the first parameter and the second parameter and the value range of the third parameter based on the Hessian matrix and the yield surface curvature algorithm, and applying the corresponding relationship and the value range to the isotropic yield criterion; transforming the isotropic yield criterion into an anisotropic yield criterion based on the generalized stress invariant on the stress tensor; predicting the material strength difference effect and anisotropic behavior based on the anisotropic yield criterion.

[0208] By executing the above method steps through a computer program, an original isotropic yield criterion can be constructed based on stress invariants. The isotropic yield criterion includes a first parameter and a second parameter for adjusting the symmetry of the third invariant of the deviator stress tensor, and a third parameter for adjusting the asymmetry of the third invariant of the deviator stress tensor. Then, the correspondence between the first parameter and the second parameter and the value range of the third parameter can be determined through the Hessian matrix and the yield surface curvature algorithm. The isotropic yield criterion after determining the parameters can be transformed into an anisotropic yield criterion to predict the material strength difference effect and anisotropic behavior. In this way, when the metal material is applied to multiple load conditions and complex stress states, the yield behavior of the metal material under complex stress states can be characterized with high precision.

[0209] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the above-mentioned module, program segment or a part of a code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flow chart, and the combination of the boxes in the block diagram or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0210] The units involved in the embodiments described in this application may be implemented by software or hardware, and the units described may also be set in a processor. The names of these units do not, in some cases, constitute limitations on the units themselves.

[0211] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the invention disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary technical means in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the claims.

Claims

1. A method for describing yield behavior, characterized in that include: An isotropic yield criterion is constructed based on the stress invariant; wherein the isotropic yield criterion includes a first parameter and a second parameter for adjusting the symmetry of the third invariant of the deviator stress tensor, and a third parameter for adjusting the asymmetry of the third invariant of the deviator stress tensor; Determine the corresponding relationship between the first parameter and the second parameter and the value range of the third parameter based on the Hessian matrix and the yield surface curvature algorithm, and apply the corresponding relationship and the value range to the isotropic yield criterion; transforming the isotropic yield criterion into an anisotropic yield criterion based on the generalized stress invariant for the stress tensor; The material strength difference effect and anisotropic behavior are predicted based on the anisotropic yield criterion.

2. The method according to claim 1, characterized in that Also includes: According to the viscoplastic self-consistent polycrystal plasticity model, the first yield point data of face-centered cubic, the second yield point data of body-centered cubic, and the third yield point data of hexagonal close-packed are generated; Based on the isotropic yield criterion, a first data curve of face-centered cubic, a second data curve of body-centered cubic, and a third data curve of hexagonal close-packed are generated; The accuracy of the isotropic yield criterion is determined based on the degree of coincidence between the first yield point data and the first data curve, the degree of coincidence between the second yield point data and the second data curve, and the degree of coincidence between the third yield point data and the third data curve.

3. The method according to claim 1, characterized in that Also includes: According to the numerical simulation model based on crystal plasticity theory, the fourth yield point data of the in-plane compression process of zirconium bell rolled plate under different pre-strains and the fifth yield point data of the thickness compression process of zirconium bell rolled plate under different pre-strains are generated; Based on the anisotropic yield criterion, a fourth data curve of the in-plane compression process of the zirconium bell rolled plate under different pre-strains and a fifth data curve of the thickness compression process of the zirconium bell rolled plate under different pre-strains are generated; Based on the degree of coincidence between the fourth yield point data and the fourth data curve, and the degree of coincidence between the fifth yield point data and the fifth data curve, the accuracy of the anisotropic yield criterion is determined.

4. The method according to claim 1, characterized in that: Also includes: Stress components representing the anisotropic yield criterion in a uniaxial tension test, a uniaxial compression test, an equibiaxial tension test, and an equibiaxial compression test; Based on the anisotropic yield criterion and each stress component, a yield stress model for each stress state is generated; wherein the yield stress model is used to characterize the relationship between the anisotropic yield criterion and the sampling angle.

5. The method according to claim 1, characterized in that Also includes: generating a plastic strain ratio coefficient for the anisotropic yield criterion; The accuracy of the anisotropic yield criterion is verified based on the plastic strain ratio coefficient.

6. The method according to claim 1, characterized in that Also includes: Based on the plastic strain ratio coefficient and the anisotropic yield criterion, constructing an error function between the prediction result and the test result; The value of the error function is minimized based on the descent simplex method to identify the anisotropic material constants in the anisotropic yield criterion.

7. The method according to claim 1, characterized in that The isotropic yield criterion is expressed as: Among them, I1 is the first invariant of the stress tensor, J2 is the second invariant of the deviator stress tensor, J3 is the third invariant of the deviator stress tensor, σ1, σ2, σ3 represent the three principal stresses, S1, S2, S3 represent the three principal deviator stresses, σ Y is the yield stress obtained by uniaxial tension, a and n are the first and second parameters for adjusting the symmetry of J3, b is the third parameter for adjusting the asymmetry of J3, μ is the parameter for adjusting the hydrostatic pressure sensitivity, and k is derived based on the uniaxial condition, which is expressed as:

8. A device for describing yielding behavior, characterized in that include: An isotropic yield criterion construction unit, used for constructing an isotropic yield criterion based on a stress invariant; wherein the isotropic yield criterion includes a first parameter and a second parameter for adjusting the symmetry of a third invariant of a deviator stress tensor, and a third parameter for adjusting the asymmetry of a third invariant of a deviator stress tensor; a parameter determination unit, configured to determine a corresponding relationship between the first parameter and the second parameter and a value range of the third parameter based on a Hessian matrix and a yield surface curvature algorithm, and apply the corresponding relationship and the value range to the isotropic yield criterion; An anisotropic yield criterion determination unit is used to transform the isotropic yield criterion into an anisotropic yield criterion based on the generalized stress invariant for the stress tensor; A prediction unit is used to predict material strength difference effect and anisotropic behavior based on the anisotropic yield criterion.

9. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

10. An electronic device, characterized in that: include: processor; as well as A memory, configured to store executable instructions of the processor; The processor is configured to perform the method of any one of claims 1 to 7 by executing the executable instructions.

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