Material plastic deformation testing method, device, equipment and medium

Abstract

The invention provides a material plastic deformation testing method, device and equipment and a medium, and relates to the technical field of calculation aided design. The method comprises the following steps: acquiring an optimal crystal plasticity parameter of a sample material; constructing a small punch experimental model and a crystal sample model of finite element simulation; performing finite element simulation according to the optimal crystal plasticity parameters, the small punch experiment model and the crystal sample model to obtain simulation data of a small punch experiment; and determining strain gradient distribution characteristics of the sample material in different plastic deformation stages based on simulation data of a small punch experiment. According to the invention, the plastic deformation behavior of the material in the small punch experiment can be simulated and analyzed more accurately, so that support is provided for reliability evaluation of equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of computer-aided design, and particularly to a method, device, equipment and medium for testing the plastic deformation of materials. Background Art

[0002] For large-scale equipment such as nuclear reactor vessels, oil transportation pipelines, and chemical production equipment that serve in extreme environments such as high temperature and pressure, nuclear radiation, and corrosive media, they are prone to creep, embrittlement, and even fracture risks during long-term operation. Therefore, regularly carrying out safety and remaining life assessments is crucial for ensuring the safe operation of the equipment. Although traditional standard test specimens can accurately obtain the mechanical property parameters of materials, they have defects such as large specimen size, difficult sampling (structures with small sizes such as thin walls), and large losses to in-service parts. In contrast, the small punch test hardly affects the structural integrity and working reliability of the in-service equipment after sampling, requires low experimental conditions, and has simple specimen preparation, providing an efficient and feasible technical path for the in-situ performance assessment of in-service equipment in extreme environments.

[0003] Through the load-displacement curve of the small punch test, the macroscopic results of the mechanical response of materials in the elastic-plastic deformation stage can be obtained. Based on finite element analysis, the stress distribution and failure mode in the microscopic deformation process can be analyzed, and the experiment can be standardized and guided by quantifying the effects of factors such as experimental results, specimen size, and friction, and the constitutive relationship and mechanical characteristics of the material can be inverted. However, in the finite element analysis of the small punch test, the traditional finite element model is limited by the homogenization hypothesis and the dependence on empirical parameters, and it is difficult to accurately capture the deformation behavior of materials dominated by slip systems and grain boundary effects at the microscopic scale. At the same time, its phenomenological constitutive model cannot characterize the anisotropic response sensitive to crystal orientation. Summary of the Invention

[0004] Embodiments of the present invention provide a method, device, equipment and storage medium for testing the plastic deformation of materials to more accurately simulate and analyze the plastic deformation behavior of materials in the small punch test, so as to provide support for the reliability assessment of the equipment.

[0005] In a first aspect, embodiments of the present invention provide a method for testing the plastic deformation of materials, including: Obtaining the optimal crystal plasticity parameters of the sample material; Constructing a small punch test model and a crystal specimen model for finite element simulation; Performing finite element simulation according to the optimal crystal plasticity parameters, the small punch test model, and the crystal specimen model to obtain the simulation data of the small punch test; Based on the simulation data of the small punch test, determining the strain gradient distribution characteristics of the sample material in different plastic deformation stages.

[0006] As a possible implementation manner, obtaining the optimal crystal plasticity parameters of the sample material includes: Obtaining the actual data of the uniaxial tensile experiment of the sample material; Using the crystal plasticity strain gradient analysis function of finite element simulation to simulate and analyze the uniaxial tensile experiment, and obtaining the simulation data of the uniaxial tensile experiment; By comparing the differences between the actual data and the simulation data of the uniaxial tensile experiment, adjusting the crystal plasticity parameters of the crystal plasticity strain gradient analysis function, and determining the crystal plasticity parameters that make the difference less than a preset threshold as the optimal crystal plasticity parameters.

[0007] As a possible implementation manner, performing finite element simulation according to the optimal crystal plasticity parameters, the small punch test model, and the crystal specimen model to obtain the simulation data of the small punch test includes: Importing the optimal crystal plasticity parameters into the crystal plasticity strain gradient analysis function of finite element simulation to determine the constitutive relationship of the sample material; Performing small punch test simulation calculations on the small punch test model and the crystal specimen model through the crystal plasticity strain gradient analysis function to obtain the simulation data of the small punch test.

[0008] As a possible implementation manner, determining the strain gradient distribution characteristics of the sample material at different plastic deformation stages based on the simulation data of the small punch test includes: Obtaining the actual data of the small punch test of the sample material; Determining the geometrically necessary dislocation distribution of the sample material at different plastic deformation stages according to the actual data and the simulation data of the small punch test.

[0009] As a possible implementation manner, constructing the crystal specimen model includes: Constructing the crystal specimen model through the Delaunay triangulation algorithm, and assigning material crystal mechanical properties and grain orientation parameters to each grain in the crystal specimen model.

[0010] As a possible implementation manner, the crystal plasticity strain gradient analysis function is constructed based on the explicit dynamic analysis stress integration algorithm.

[0011] As a possible implementation manner, both the actual data and the simulation data of the uniaxial tensile experiment are load-displacement curves; The crystal plasticity parameters include: elastic constant, reference shear strain rate, rate sensitivity index, initial yield stress of the slip system, saturation stress of the slip system, and initial yield hardening modulus of the slip system.

[0012] In a second aspect, an embodiment of the present invention provides a material plastic deformation testing device, including: An acquisition module, configured to acquire the optimal crystal plasticity parameters of a sample material; A construction module, configured to construct a small punch test model and a crystal specimen model for finite element simulation; A simulation module, configured to perform finite element simulation according to the optimal crystal plasticity parameters, the small punch test model, and the crystal specimen model to obtain simulation data of the small punch test; A determination module, configured to determine the strain gradient distribution characteristics of the sample material in different plastic deformation stages based on the simulation data of the small punch test.

[0013] In a third aspect, an embodiment of the present invention provides an electronic device, including a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, the method in the first aspect or any possible implementation manner of the first aspect is implemented.

[0014] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method in the first aspect or any possible implementation manner of the first aspect is implemented.

[0015] In the embodiment of the present invention, by acquiring the optimal crystal plasticity parameters of a sample material and combining the crystal plasticity constitutive relationship with finite element, local stress concentration and non-uniform plastic deformation behavior caused by grain orientation differences can be captured; based on the pseudo-random grain modeling technique, a crystal specimen model is constructed to quantify the contribution of microscopic mechanisms such as grain boundary effects to the macroscopic mechanical response; finite element simulation is performed according to the optimal crystal plasticity parameters, the small punch test model, and the crystal specimen model, and based on the simulation data of the small punch test, the strain gradient distribution characteristics of the sample material in different plastic deformation stages are calculated, so as to accurately simulate and analyze the plastic deformation behavior of the material in the small punch test and provide support for the reliability assessment of the device. Description of the Drawings

[0016] Figure 1 is a schematic diagram of a load-displacement curve provided by an embodiment of the present invention; Figure 2 is a schematic diagram of the geometrically necessary dislocation distribution of a small punch test provided by an embodiment of the present invention; Figure 3 is a schematic diagram of the finite element simulation of a small punch test provided by an embodiment of the present invention; Figure 4 is a schematic flowchart of a material plastic deformation testing method provided by an embodiment of the present invention; Figure 5 is a schematic diagram of curve comparison provided by an embodiment of the present invention; Figure 6 It is a schematic diagram of the small punch test model provided by the embodiment of the present invention; Figure 7 It is a schematic diagram of the crystal specimen model provided by the embodiment of the present invention; Figure 8 It is a schematic flow chart of the material plastic deformation testing method provided by another embodiment of the present invention; Figure 9 It is a schematic structural diagram of the material plastic deformation testing device provided by the embodiment of the present invention; Figure 10 It is a schematic diagram of the electronic device provided by the embodiment of the present invention. Detailed implementation manners

[0017] Next, the embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0018] First, a brief introduction to the small punch test is given.

[0019] The small punch test is a miniaturized testing technique for evaluating the mechanical properties of materials (such as strength, plasticity, toughness, etc.). Compared with traditional experiments such as tension and impact, its greatest feature is that it only requires a circular thin sheet specimen with a tiny size (usually with a diameter of 2 - 10 mm and a thickness of 0.1 - 2 mm). Therefore, it is particularly suitable for scenarios where it is difficult to obtain material samples (such as non-destructive testing of in-service components, research on small-sized materials) or rapid evaluation is needed. Its basic principle is: place the circular thin sheet specimen on a base with a circular hole, and apply a vertical load at a constant rate through a punch at the top (usually a hemispherical or cylindrical indenter), causing the specimen to undergo bending deformation until it fractures. Record the load-displacement curve, and evaluate the material properties through curve characteristics (such as peak load, fracture displacement, energy absorption, etc.).

[0020] Exemplarily, the load-displacement curve of the small punch test can be seen in Figure 1 as shown. Its deformation process can be divided into six stages: elastic deformation stage I, plastic bending stage II, uniform plastic deformation stage III, plastic deformation instability stage IV, local necking instability stage V, and fracture failure stage VI. Analyzing the mechanical behavior through these six stages can replace the traditional unidirectional tensile test to evaluate the mechanical properties such as the elastic-plastic behavior of materials, greatly improving the detection efficiency of in-service special equipment.

[0021] In the embodiment of the present invention, the small punch specimen is circular, with a diameter of 8 mm and a thickness of 0.5 mm. Since there are non-uniform deformations in both the thickness and radius directions of the small punch with a thickness of 0.5 mm, it is of great significance to analyze the influence of the strain gradient. The load-displacement curve obtained from the small punch experiment can only obtain the macroscopic results of the mechanical response in the elastic-plastic deformation stage of the material. However, the finite element analysis based on crystal plasticity theory can achieve the analysis of the stress distribution and failure mode in the microscopic deformation process, quantify the influence of experimental results, specimen size, friction, etc. to standardize and guide the experiment, and invert the constitutive relationship and mechanical properties of the material, etc.

[0022] Figure 2 It is a schematic diagram of the distribution of geometrically necessary dislocations during the small punch experiment. Figure 3 It is the finite element simulation model during the small punch experiment. Figure 3 The load condition of the small punch specimen can be described by the load concentration region Z. That is, during the deformation process of the small punch specimen, the upper surface is subjected to the load from the punch, that is, the upper surface is initially compressed, and the lower surface is subjected to tensile deformation. That is, the specimen contracts in strain along the upper surface of the cross-section, and the lower surface elongates in strain. That is, there is a strain difference between the upper and lower surfaces. This strain difference divided by the distance between the upper and lower surfaces is defined as the strain gradient. The degree of strain change in the thickness direction of the sheet material can be described by the strain gradient. At the microscale, the plastic deformation mechanism of metals is mainly the slip of dislocations occurring along different slip systems. Assume that there are Figure 2 three layers of grains as shown in the figure, where β are the geometrically necessary dislocations generated to maintain the bending deformation state. The dislocations generated due to maintaining the shape are the main reason for generating the strain gradient. At the same time, due to the generation of this part of dislocations, the dislocation density of the specimen increases, which in turn causes lattice distortion and plays a role in strengthening the material. The smaller the thickness, the greater the influence of the strain gradient. For example, there is a greater influence in the processes of plastic deformation with non-uniformity such as micro-bending, micro-torsion, and micro-indentation. In this microscale, that is, when the size is in the state of a few micrometers to a few hundred micrometers, the influence of the geometrically necessary dislocation density on plastic deformation cannot be ignored. Therefore, the finite element analysis based on crystal plasticity theory can be used to evaluate the strain gradient distribution related to the geometrically necessary dislocation density during the non-uniform plastic deformation of the specimen.

[0023] See Figure 4 , which shows the implementation flowchart of the material plastic deformation testing method provided by the embodiment of the present invention, and is described in detail as follows: Step S401, obtain the optimal crystal plasticity parameters of the sample material.

[0024] In the finite element analysis of the small punch test, due to its homogenization assumption and dependence on empirical parameters, the traditional finite element model is difficult to accurately capture the deformation behavior dominated by microscale slip systems and grain boundary effects in materials. At the same time, its phenomenological constitutive model cannot characterize the anisotropic response sensitive to crystal orientation. Therefore, it is necessary to develop a reasonable constitutive relationship considering microcrystalline characteristics and apply it to the finite element analysis of the small punch test to promote the model analysis combining macro and micro scales.

[0025] Based on the crystal plasticity theory of strain gradient strengthening, this embodiment conducts multi-scale simulation of the small punch test by combining the simulated crystal plasticity strain gradient analysis function (i.e., the VUMAT subroutine) to obtain the optimal crystal plasticity parameters of the sample material, thereby establishing a constitutive relationship considering the dynamic evolution of geometrically necessary dislocations. And by developing a VUMAT subroutine based on the stress integration algorithm of explicit dynamic analysis, the cross-scale correlation analysis of material micro-plastic deformation and macro-mechanical response is realized.

[0026] For example, in a possible implementation, the process of obtaining the optimal crystal plasticity parameters of the sample material is as follows: Obtain the actual data of the uniaxial tensile test of the sample material; Using the crystal plasticity strain gradient analysis function of finite element simulation, simulate and analyze the uniaxial tensile test to obtain the simulation data of the uniaxial tensile test; By comparing the differences between the actual data and the simulation data of the uniaxial tensile test, adjust the crystal plasticity parameters of the crystal plasticity strain gradient analysis function, and determine the crystal plasticity parameters that make the difference less than a preset threshold as the optimal crystal plasticity parameters.

[0027] In the embodiment of the present invention, the macroscopic constitutive characteristics of the material are first obtained through the uniaxial tensile test. In this process, the load-displacement curve of the material is obtained, which can lay the foundation data for subsequent numerical simulations. Further, the VUMAT subroutine is used to perform finite element simulation on the uniaxial tensile test. In this process, by continuously fitting the crystal plasticity parameters, a set of optimal parameters with highly consistent simulation data and actual data are ensured, so that the constitutive relationship obtained by simulation has the highest similarity with the actual experimental results, as Figure 5 shown. The accuracy and reliability of the parameters are ensured through the process of repeated iteration. After obtaining the optimal crystal plasticity parameters, they can be applied to the simulation of more complex deformation problems - the small punch test.

[0028] Step S402, construct a finite element simulation model of the small punch test and a crystal specimen model.

[0029] The small punch test is a typical complex plastic deformation process. Through finite element simulation, the characteristics of the strain gradient distribution inside it can be deeply explored. This step not only verifies the effectiveness of the optimal crystal plasticity parameters but also expands the research scope from simple unidirectional tension to more complex three-dimensional deformation conditions. For the finite element simulation model of the small punch test, see Figure 6 , and for the crystal specimen model, see Figure 7 (It is found through numerical simulation that the different stages experienced by a circular specimen during plastic deformation can be equivalently represented by the plastic deformation process of a square specimen).

[0030] The crystal specimen model here can be a single crystal specimen model or a polycrystalline specimen model. For example, in a possible implementation, a polycrystalline specimen model can be constructed through the Thiessen polygon algorithm (i.e., Voronoi diagram), and material crystal mechanical properties and grain orientation parameters are assigned to each grain in the crystal specimen model. Then, through finite element analysis software, numerical simulations can be performed for different plastic deformation stages during the experiment to obtain the plastic deformation characteristics of different plastic deformation stages. Further, by combining strain gradient analysis and verifying the model accuracy through experimental comparison, the combination of the mechanism of plastic inhomogeneous deformation of thin plates at the microscale and numerical simulation research can be promoted.

[0031] Step S403: Based on the optimal crystal plasticity parameters, the small punch test model, and the crystal specimen model, perform finite element simulation to obtain the simulation data of the small punch test.

[0032] In this embodiment, by importing the optimal crystal plasticity parameters into the VUMAT subroutine of the finite element simulation, the constitutive relationship of the sample material is determined. The VUMAT subroutine performs simulation calculations on the small punch test to obtain the simulation data of the small punch test.

[0033] Step S404: Based on the simulation data of the small punch test, determine the strain gradient distribution characteristics of the sample material at different plastic deformation stages.

[0034] Exemplarily, the actual data of the small punch test can be compared and analyzed with the simulation data of the finite element simulation. By carefully studying the strain gradient distribution characteristics at different plastic deformation stages, the microscopic deformation mechanism of the material under complex loading conditions can be revealed. For example, the geometrically necessary dislocation distribution related to the strain gradient is obtained, where the geometrically necessary dislocation density in the actual failure area (i.e., the fracture area) of the sample material is the largest and the distribution is the densest.

[0035] In the embodiments of the present invention, by obtaining the optimal crystal plasticity parameters of the sample material and combining the crystal plasticity constitutive relationship with the finite element method, the local stress concentration and non-uniform plastic deformation behavior caused by the grain orientation difference can be captured; based on the pseudo-random grain modeling technology, a crystal specimen model is constructed to quantify the contribution of microscopic mechanisms such as grain boundary effects to the macroscopic mechanical response; according to the optimal crystal plasticity parameters, the small punch test model and the crystal specimen model, finite element simulation is carried out, and based on the simulation data of the small punch test, the strain gradient distribution characteristics of the sample material at different plastic deformation stages are calculated, so as to accurately simulate and analyze the plastic deformation behavior of the material in the small punch test and provide support for the reliability evaluation of the equipment.

[0036] The following uses a specific example to explain the implementation process of the material plastic deformation test method proposed in the embodiments of the present invention.

[0037] See Figure 8 As shown, the material plastic deformation test method includes: (1) Write code using a programming language to establish a VUMAT subroutine based on the explicit dynamics analysis stress integration algorithm, so that in the finite element software, the VUMAT subroutine can be called for calculation during operation, and the shear strain gradient of the non-uniform deformation of the grains and the geometrically necessary dislocation density related thereto can be obtained, and the cross-scale correlation analysis of the microscopic plastic deformation and macroscopic mechanical response of the material can be realized.

[0038] (2) Conduct a uniaxial tensile test on the sample material to obtain the load-displacement curve of the sample material.

[0039] (3) In the finite element software, simulate the uniaxial tensile test process, and call the VUMAT subroutine during the simulation to obtain the crystal plasticity parameters for the simulation of the small punch test. Select a set of parameters with a high experimental simulation coincidence degree in the load-displacement curve as the optimal parameters, and the parameters include: elastic constant, reference shear strain rate, rate sensitivity index, initial yield stress of the slip system, saturation stress of the slip system, and initial yield hardening modulus of the slip system.

[0040] (4) Construct a small punch test model and a crystal specimen model for finite element simulation, and assign material crystal mechanical properties and grain orientation parameters to each grain in the crystal specimen model to consider the influence of these two factors during the plastic deformation process.

[0041] (5) Import the optimal crystal plasticity parameters obtained in step 3 into the finite element software, and obtain the numerical analysis results of the small punch test through simulation analysis, including the plastic deformation characteristics of the small punch specimen at different deformation stages, such as the distribution of geometrically necessary dislocations related to the strain gradient.

[0042] The embodiments of the present invention have the following advantages: Combining crystal plasticity finite element with small punch test, through the comparison between crystal plasticity strain gradient finite element numerical simulation and experiment, optimizing material constitutive parameters and revealing microscopic deformation mechanisms, significantly improving the prediction accuracy of complex deformation; In the process of finite element analysis, the dynamic explicit algorithm is used to avoid the convergence difficulties caused by nonlinear problems in implicit analysis. At the same time, combined with the nonlinear crystal specimen model, it can characterize the evolution process of microscopic characteristics of complex plastic deformation; By introducing the dislocation density evolution model, the strain gradient crystal plasticity numerical simulation method is extended in the study of plastic deformation of micro- / nano-scale materials. Further, thermal fields, etc. can be added in the finite element simulation to simulate the degradation behavior of material properties under extreme environments, thus providing research ideas for the efficient design and life assessment of equipment.

[0043] It should be understood that the magnitudes of the sequence numbers of the steps in the above embodiments do not mean the order of execution. The order of execution of each process should be determined according to its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present invention.

[0044] The following is the device embodiment of the present invention. For the details not described in detail, reference can be made to the corresponding method embodiments above.

[0045] Figure 9 The structural schematic diagram of the material plastic deformation test device provided by the embodiment of the present invention is shown. For the convenience of description, only the parts related to the embodiment of the present invention are shown and are described in detail as follows: As Figure 9 shown, the material plastic deformation test device 9 includes: An acquisition module 91, configured to acquire the optimal crystal plasticity parameters of the sample material; A construction module 92, configured to construct a small punch test model and a crystal specimen model for finite element simulation; A simulation module 93, configured to perform finite element simulation according to the optimal crystal plasticity parameters, the small punch test model and the crystal specimen model, and obtain the simulation data of the small punch test; A determination module 94, configured to determine the strain gradient distribution characteristics of the sample material in different plastic deformation stages based on the simulation data of the small punch test.

[0046] As a possible implementation manner, the acquisition module 91 is used for: Acquiring the actual data of the uniaxial tensile test of the sample material; Using the crystal plasticity strain gradient analysis function of finite element simulation to perform simulation analysis on the uniaxial tensile test, and obtaining the simulation data of the uniaxial tensile test; By comparing the differences between the actual data and the simulation data of the uniaxial tensile test, adjusting the crystal plasticity parameters of the crystal plasticity strain gradient analysis function, and determining the crystal plasticity parameters that make the difference less than a preset threshold as the optimal crystal plasticity parameters.

[0047] As a possible implementation, the simulation module 93 is used for: Import the optimal crystal plasticity parameters into the crystal plasticity strain gradient analysis function of the finite element simulation to determine the constitutive relationship of the sample material; Through the crystal plasticity strain gradient analysis function, perform small punch test simulation calculations on the small punch test model and the crystal specimen model to obtain the simulation data of the small punch test.

[0048] As a possible implementation, the determination module 94 is used for: Obtain the actual data of the small punch test of the sample material; According to the actual data and simulation data of the small punch test, determine the geometrically necessary dislocation distribution of the sample material in different plastic deformation stages.

[0049] As a possible implementation, the construction module 92 is used for: Construct a crystal specimen model through the Delaunay triangulation algorithm, and assign material crystal mechanical properties and grain orientation parameters to each grain in the crystal specimen model.

[0050] As a possible implementation, the crystal plasticity strain gradient analysis function is constructed based on the explicit dynamics analysis stress integration algorithm.

[0051] As a possible implementation, the actual data and simulation data of the uniaxial tensile test are both load-displacement curves; The crystal plasticity parameters include: elastic constants, reference shear strain rate, rate sensitivity index, initial yield stress of the slip system, saturation stress of the slip system, initial yield hardening modulus of the slip system.

[0052] In the embodiments of the present invention, by obtaining the optimal crystal plasticity parameters of the sample material and combining the crystal plasticity constitutive relationship with the finite element, the local stress concentration and uneven plastic deformation behavior caused by the grain orientation difference can be captured; based on the pseudo-random grain modeling technology, a crystal specimen model is constructed to quantify the contribution of micro-mechanisms such as grain boundary effects to the macroscopic mechanical response; according to the optimal crystal plasticity parameters, the small punch test model and the crystal specimen model, finite element simulation is performed, and based on the simulation data of the small punch test, the strain gradient distribution characteristics of the sample material in different plastic deformation stages are calculated, so as to accurately simulate and analyze the plastic deformation behavior of the material in the small punch test and provide support for the reliability assessment of the equipment.

[0053] Figure 10 It is a schematic diagram of the electronic device 10 provided by the embodiments of the present invention. As Figure 10As shown, the electronic device 10 of this embodiment includes: a processor 100 and a memory 101. The memory 101 stores a computer program 102. When the processor 100 executes the computer program 102, the steps in the above-mentioned method embodiments are implemented. Alternatively, when the processor 100 executes the computer program 102, the functions of each module / unit in the above-mentioned device embodiments are implemented.

[0054] Exemplarily, the computer program 102 can be divided into one or more modules / units. The one or more modules / units are stored in the memory 101 and executed by the processor 100 to complete the present invention. The one or more modules / units can be a series of computer program instruction segments capable of performing specific functions, and these instruction segments are used to describe the execution process of the computer program 102 in the electronic device 10.

[0055] The electronic device 10 may include, but is not limited to, a processor 100 and a memory 101. Those skilled in the art can understand that Figure 10 merely examples of the electronic device 10, which do not constitute a limitation on the electronic device 10. It may include more or fewer components than shown in the figure, or combine certain components, or different components. For example, the electronic device 10 may also include input / output devices, network access devices, buses, etc.

[0056] The processor 100 may be a central processing unit (CPU), or may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0057] The memory 101 can be an internal storage unit of the electronic device 10, such as the hard disk or memory of the electronic device 10. The memory 101 can also be an external storage device of the electronic device 10, such as a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) card, a Flash Card, etc. equipped on the electronic device 10. Further, the memory 101 can also include both the internal storage unit of the electronic device 10 and the external storage device. The memory 101 is used to store the computer program 102 and other programs and data required by the electronic device 10. The memory 101 can also be used to temporarily store the data that has been output or will be output.

[0058] For the convenience and simplicity of description, only the above division of each functional module / unit is used as an example. In practical applications, the above functions can be allocated to different functional modules / units according to needs. The above modules / units can be implemented in the form of hardware, or in the form of software, or in the form of a combination of hardware and software.

[0059] The embodiment of the present invention also provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, the methods in the above method embodiments are implemented.

[0060] The embodiment of the present invention also provides a computer program product, including a computer program. When the computer program is executed by a processor, the methods in the above method embodiments are implemented.

[0061] Among them, the computer program includes computer program code, and the computer program code can be in the form of source code, object code, executable file or some intermediate form, etc. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, and software distribution medium, etc.

[0062] In the above embodiments, the descriptions of each embodiment have their own emphases. For the parts not detailed or recorded in a certain embodiment, reference can be made to the relevant descriptions of other embodiments. If there is no special explanation and logical conflict, the terms and / or descriptions between different embodiments are consistent and can be mutually referenced, and the technical features in different embodiments can be combined to form new embodiments according to their internal logical relationships.

[0063] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A method for testing the plastic deformation of a material, characterized in that, including: obtaining the optimal crystal plasticity parameters of the sample material; constructing a small punch test model and a crystal specimen model for finite element simulation; performing finite element simulation according to the optimal crystal plasticity parameters, the small punch test model and the crystal specimen model to obtain the simulation data of the small punch test; determining the strain gradient distribution characteristics of the sample material in different plastic deformation stages based on the simulation data of the small punch test.

2. The method for testing the plastic deformation of a material according to claim 1, characterized in that The obtaining the optimal crystal plasticity parameters of the sample material includes: obtaining the actual data of the uniaxial tensile test of the sample material; using the crystal plasticity strain gradient analysis function of finite element simulation to perform simulation analysis on the uniaxial tensile test to obtain the simulation data of the uniaxial tensile test; by comparing the differences between the actual data and the simulation data of the uniaxial tensile test, adjusting the crystal plasticity parameters of the crystal plasticity strain gradient analysis function, and determining the crystal plasticity parameters that make the difference less than a preset threshold as the optimal crystal plasticity parameters.

3. The method for testing the plastic deformation of materials according to claim 1, characterized in that The performing finite element simulation according to the optimal crystal plasticity parameters, the small punch test model and the crystal specimen model to obtain the simulation data of the small punch test includes: importing the optimal crystal plasticity parameters into the crystal plasticity strain gradient analysis function of finite element simulation to determine the constitutive relationship of the sample material; performing small punch test simulation calculations on the small punch test model and the crystal specimen model through the crystal plasticity strain gradient analysis function to obtain the simulation data of the small punch test.

4. The method for testing the plastic deformation of materials according to claim 1, characterized in that, The determining the strain gradient distribution characteristics of the sample material in different plastic deformation stages based on the simulation data of the small punch test includes: obtaining the actual data of the small punch test of the sample material; determining the geometrically necessary dislocation distribution of the sample material in different plastic deformation stages according to the actual data and the simulation data of the small punch test.

5. The method for testing the plastic deformation of a material according to any one of claims 1 to 4, characterized in that, The constructing the crystal specimen model includes: constructing the crystal specimen model through the Delaunay triangulation algorithm and assigning material crystal mechanical properties and grain orientation parameters to each grain in the crystal specimen model.

6. The method for testing the plastic deformation of a material according to claim 2 or 3, characterized in that The crystal plasticity strain gradient analysis function is constructed based on the explicit dynamics analysis stress integration algorithm.

7. The method for testing the plastic deformation of a material according to claim 2, characterized in that, Both the actual data and the simulation data of the uniaxial tensile test are load-displacement curves; The crystal plasticity parameters include: elastic constants, reference shear strain rate, rate sensitivity index, initial yield stress of slip system, saturation stress of slip system, initial yield hardening modulus of slip system.

8. A device for testing the plastic deformation of a material, characterized in that, including: an obtaining module for obtaining the optimal crystal plasticity parameters of the sample material; a constructing module for constructing a small punch test model and a crystal specimen model for finite element simulation; a simulation module for performing finite element simulation according to the optimal crystal plasticity parameters, the small punch test model and the crystal specimen model to obtain the simulation data of the small punch test; a determining module for determining the strain gradient distribution characteristics of the sample material in different plastic deformation stages based on the simulation data of the small punch test.

9. An electronic device, characterized in that, It includes a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, the method described in any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method described in any one of claims 1 to 7 is implemented.

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