A deform-based damage simulation method

Abstract

The application discloses a damage simulation method based on deform, which comprises the following steps: a macro flow stress constitutive model is established according to stress-strain curves and experimental data of fracture strain under different temperatures and stretching speeds; a material library based on Deform is established by combining basic properties of elastic parameters and thermal performance parameters of the material; a damage prediction module for predicting a forging hot forming process is established, a ductile fracture criterion model is established according to obtained data of influences of the temperature and the strain rate on the strain at the time of fracture, and the temperature, the strain rate in the forging process and fracture in the forming process are predicted.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of damage simulation of high temperature forging of high strength aluminum alloy in metal plastic forming, and in particular to a damage simulation method based on DEFORM. BACKGROUND

[0002] Although the plasticity of high strength aluminum alloy is improved at high temperature, it is still prone to fracture defects in the forming process, which directly causes the parts to be scrapped, wastes the research and development, and increases the research and development time. Different materials have different plastic limits, so the fracture conditions in the forming process of different materials under the same process conditions are different, and it is necessary to predict in advance that the material is fractured in the forming process. Therefore, accurate simulation of the fracture condition in the metal plastic forming process is of great significance to die and process design.

[0003] Currently, the main software for simulating the fracture damage in the metal plastic forming process is DYNAFORM and DEFORM, which has multiple ductile fracture criteria built-in, and the user needs to input the relevant material parameters and critical damage coefficients, and the software automatically calculates the damage value through simulation. However, the ductile fracture criteria provided by the system are one-sided and insufficient to describe the fracture conditions of all forming processes under high temperature forging. Currently, for the ductile fracture criterion, researchers have developed a series of modified models based on the classic ductile fracture criterion, which are more suitable for fracture description under specific conditions. However, for forging under high temperature conditions, DYNAFORM and DEFORM cannot well handle new fracture models, and complex programming is required to achieve it (Feng Wei, Hua Lin, Han Xinghui, et al. A prediction method for microstructure evolution of 20CrMnTiH steel during hot deformation process:.) And the simulation of fracture through secondary development of DEFORM is more simple and flexible (Fu Xiuli. Method for judging thickness of DEFORM-3D simulation turning surface grain refinement layer:, 2015.). SUMMARY

[0004] In view of the above problems, the present application aims to provide a simulation method for simulating fracture in forging based on secondary development of DEFORM, and a prediction method for fracture in the forming process considering the influence of temperature and strain rate on fracture according to different conditions, which improves the accuracy of simulation.

[0005] The present application is realized by at least one of the following technical solutions.

[0006] A damage simulation method based on DEFORM, comprising the following steps:

[0007] According to the stress-strain curve, the experimental data of the strain at break under different temperatures and stretching speeds, a macroscopic flow stress constitutive model is established;

[0008] In combination with the basic properties of the elastic parameters and thermal performance parameters of the material, a material library based on Deform is established;

[0009] According to the obtained data of the influence of temperature and strain rate on the strain at break, a ductile fracture criterion model is established, a damage prediction module for predicting the hot forming process of forging is established, and whether fracture occurs in the forging process is predicted.

[0010] Further, the damage prediction module is used to judge whether fracture occurs in the forging process and the fracture position, and specifically comprises:

[0011] It is judged whether the forging is being deformed, i.e., whether the strain rate is less than or equal to 0, and when the strain rate is less than or equal to 0, the damage calculation is ended;

[0012] When the damage module starts to calculate, it is judged whether the stress is less than 0, and when the stress is less than 0, the damage calculation is ended, so as to judge whether the forging process is ended;

[0013] When the damage module starts to calculate, if the strain rate is greater than 0 and the stress σ is greater than 0, the damage calculation is started, and the damage value calculation is based on the ductile fracture criterion;

[0014] After the calculation is completed, the damage value DAMG is returned to the main program and stored in a data file;

[0015] According to the size of the material, the forming process, a finite element model for simulation is established,

[0016] The finite element model is imported into the Deform pre-processing module for assembly, and the material type, simulation type, mesh division, constitutive model, fracture criterion, yield criterion, temperature, motion direction and other process parameter settings are set, and after the setting is completed, the DB file is generated and saved;

[0017] In the simulator module, the solution is calculated, and in the post-processing analysis module, the solution result is loaded, and the metal flow rule, damage condition and temperature change condition are analyzed.

[0018] Further, the parameters include material constitutive model parameters, fracture criterion parameters, simulation control process parameters, mold motion speed and direction, assembly relationship, mesh division quantity, and related parameters of the initial temperature of the material.

[0019] Further, when the parameters are set, the part about the damage and fracture criterion needs to select the corresponding development model number.

[0020] Further, the ductile fracture criterion formula is:

[0021]

[0022] Wherein, epsilon f is the true strain at fracture, sigma * is the maximum principal stress, is the equivalent stress, T is the temperature, is the strain rate, represents the equivalent strain, D is the damage factor, is the damping coefficient, which is a function of temperature T and strain rate m1 is the influence factor of temperature on damage factor, m2 is the influence factor of strain rate on damage fracture, A and B are material coefficients.

[0023] Further, the temperature when calculating the damage value is the temperature of the integral point, and the integral point temperature is obtained by using the node temperature.

[0024] Further, the integral point temperature is denoted as T;

[0025]

[0026] Wherein, TEMPE(1), TEMPE(2), TEMPE(3), TEMPE(4), TEMPE(5), TEMPE(6), TEMPE(7), TEMPE(8) represent 8 values of the public variable node temperature referenced by the public region command.

[0027] Further, the constitutive model is:

[0028]

[0029] Wherein is the strain rate, R is the gas constant, T is the absolute temperature, Q is the activation energy in the thermal deformation process, sigma is the corresponding flow stress value under the given strain value, A, alpha and n are all material constants that need to be measured in experiments.

[0030] Further, before the model is predicted, the model is meshed and the initial temperature of the model is defined according to the size of the material, the forming process and the establishment of the finite element model of simulation simulation.

[0031] Further, the simulation mode is set to heat transfer, and the heat dissipation mode is free heat dissipation.

[0032] Compared with the prior art, the beneficial effects of the present application are:

[0033] Compared with the toughness fracture criterion of the system itself, the application considers the influence of temperature and speed on the fracture in the high-temperature forging process, and the fracture criterion can improve the accuracy of simulation analysis, avoid unnecessary process parameter experiments in the actual production process, and provide a theoretical basis for the design and optimization of molds and parts. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 is the damage result graph of example 1;

[0035] Figure 2 is the damage result graph of example 2;

[0036] Figure 3 is the damage result graph of example 3;

[0037] Figure 4 is the flow chart of a damage simulation method based on deform of the example.

[0038] Figure 5 is the calculation flow chart of a damage simulation method based on deform of the example. DETAILED DESCRIPTION

[0039] The application will be further described below in combination with the drawings and specific examples. The preferred embodiments of the application are shown in the drawings, and the drawings serve to supplement the description in the text part of the specification, so that people can intuitively and visually understand each technical feature and the overall technical scheme of the application. However, it cannot be understood as a limitation on the protection scope of the application.

[0040] The damage simulation method based on deform of the application comprises the following steps:

[0041] First, a three-dimensional model is obtained through corresponding CAD and three-dimensional software, and an stl format is exported. The stl format three-dimensional model is imported through deform, and the selection of the fracture criterion should select the corresponding number of secondary development; second, Fortran language is used for secondary development and compilation to generate a DEF_SIM_64.exe file to replace the DEF_SIM_64.exe file in the 3D folder of the installation directory. The program automatically reads the data required for fracture criterion calculation, and returns the damage value to the main program for post-processing display through the return statement after the calculation is completed. The related number of the toughness fracture criterion developed in the secondary development process should be noted.

[0042] Example 1

[0043] The damage simulation method based on deform comprises the following steps:

[0044] S1, high temperature tensile experiment of 7050 aluminum alloy is carried out to obtain stress-strain curves and fracture strain experimental data at different temperatures and tensile speeds;

[0045] S2, a macro flow stress constitutive model arrhenius is established by the experimental data obtained in step S1; and a material library based on Deform is established by combining basic properties such as elastic parameters and thermal performance parameters of the material;

[0046] The arrhenius constitutive model is as follows:

[0047]

[0048] Wherein is the strain rate (s -1 ), R is the gas constant (KJ / mol), T is the absolute temperature (K), Q is the activation energy in the thermal deformation process (KJ / mol), σ is the flow stress value corresponding to a given strain value (MPa), A (s -21 ), α (MPa) and n are all material constants to be measured in the experiment.

[0049] S3, a damage prediction module for predicting the forging hot forming process is established by using the finite element theory of metal plastic forming, and a ductile fracture criterion model is established according to the influence data of temperature and strain rate on strain at fracture obtained in step S1. The fracture criterion coupled with temperature and strain rate is written into the Deform simulation software by using Fortran language and the secondary development document DEF_SIM (user-defined calculation) provided by the Deform simulation software, so as to realize the high temperature forging damage prediction, and the Deform software after secondary development can more accurately predict the influence of temperature and strain rate on fracture in the forging forming process;

[0050] The damage prediction module is used to judge whether fracture occurs in the forging process and the position of the fracture, and specifically includes the following steps:

[0051] When the damage prediction module starts to run, the input strain rate, stress and step time are read, and then it is judged whether the forging is deforming, that is, whether the strain rate is less than or equal to 0. When the strain rate is less than or equal to 0, the damage calculation is ended;

[0052] It is judged whether the stress is less than 0. When the stress is less than 0, the damage calculation is ended, and the current damage value is returned to the main program, and the damage value calculation is ended;

[0053] If the strain rate is greater than 0 and the stress σ is greater than 0, the damage value calculation is started, and the damage value calculation is calculated according to the ductile fracture criterion;

[0054] The common variable unit node temperature TEMPE (8) is called by the common statement at the beginning of the calculation, TEMPE (8) has 8 values, TEMPE (1), TEMPE (2), TEMPE (3), TEMPE (4), TEMPE (5), TEMPE (6), TEMPE (7), TEMPE (8), the temperature used for calculating the damage value is the unit temperature T, which is obtained by solving the node temperature, and the related formula is:

[0055]

[0056] After the temperature calculation is completed, the maximum principal stress calculation subroutine MAXPRN3 (STSE, PRNSTS, IFLAG, HY) (maximum principal stress (stress, maximum principal stress, root criterion, hydrostatic stress)) is called by the call statement to calculate the damage value according to the fracture criterion.

[0057] The ductile fracture criterion is:

[0058]

[0059] Where, ε f is the true strain at fracture, σ * is the maximum principal stress, is the equivalent stress, T is the temperature, is the strain rate, D is the damage factor, is the damping coefficient, which is a function of temperature and strain rate, m1 is the temperature influence factor on the damage factor, m2 is the strain rate influence factor on the damage fracture, A and B are material coefficients;

[0060] After the S4 calculation is completed, the damage value DAMG is returned to the main program and stored in the data file;

[0061] S5, according to the size of the material, the forming process, the finite element model of the simulation is established, the finite element model is imported into the existing pre-processing module of Deform for assembly, and the material type, simulation type (forming, heat transfer, heat treatment), mesh division, constitutive model, fracture criterion, yield criterion, temperature, motion direction and other process parameter settings are set, and the DB file is generated after the setting is completed;

[0062] S6, in the simulator (calculation and solution) module operation and solution, then load the solution result in the post-processing analysis module, analyze the metal flow rule, damage condition, temperature change condition, can more accurately judge the probability and position of the rupture generated in the forming process, the damage simulation result of the embodiment is shown in Figure 1 .

[0063] Implementation column 2

[0064] A damage simulation method based on deform, comprising the following steps:

[0065] S1, high temperature tensile experiment is carried out on 7075 aluminum alloy to obtain stress-strain curve, fracture strain experimental data under different temperature and tensile speed;

[0066] S2, the experimental data obtained by step S1 is used to establish a macro flow stress constitutive model arrhenius;Combined with the basic properties of material elastic parameters and thermal performance parameters, the material library based on Deform is established;

[0067] The arrhenius constitutive model is:

[0068]

[0069] The strain rate (s -1 ), R is gas constant (KJ / mol), T is absolute temperature (K), Q is the activation energy in thermal deformation process (KJ / mol), σ is the corresponding flow stress value (MPa) under given strain value, A (s -21 ), α (MPa) and n are material constants measured in experiment.

[0070] S3, according to the size of material, forming process, the finite element model of simulation is established, including upper die, lower die, blank;

[0071] S4, open Deform pre-processing module, unit selection SI standard, the stage name is Loading (loading) import blank finite element model, set simulation mode to heat transfer, heat dissipation mode is free heat dissipation;Set the contact condition, according to the actual blanking process of the blank and air contact surface to choose, in this embodiment, all the external surface of the blank is in contact with air;Set the material properties of the blank, heat dissipation coefficient, constitutive model arrhenius;Mesh division is carried out on the blank, and the initial temperature of the blank is defined;

[0072] S5, define the total analysis step, the heat dissipation process analysis step is usually 10-20 steps, this embodiment is 10 steps;According to the actual process, the blank needs 10s from heating furnace to lower die, the step length is set to time control, and the time of each step is 1s;

[0073] S6, click Database Generation, check settings (Chek), if prompted to generate data, click Generate to generate DB data file, otherwise, change the settings according to the relevant prompt;After generating data, save and exit the pre-processing module;

[0074] S7, enter the simulator module to submit the operation, and wait for the calculation result;

[0075] S8, design a damage prediction module for predicting the forging hot forming process, design a secondary development subprogram flowchart for damage prediction by using the finite element theory of metal plastic forming, establish a ductile fracture criterion model according to the data of the influence of temperature and strain rate on strain at fracture obtained in step S1, write a user subprogram by using Fortran language and the secondary development document DEF_SIM (user-defined calculation) provided by the Deform simulation software, embed the Deform software for secondary development, so that the Deform software after secondary development can more accurately predict the influence of temperature and strain rate on fracture in the forging forming process; in the embodiment, the deform secondary development compiler is absoft Fortran V9.0 / 11.0, the secondary development is in the specified usr_dmg.f file, the maximum principal stress calculation subprogram MAXPRN3 is called by using the call statement in usr_dmg.f, and the global variable unit temperature TEMPE is referred by using the common statement. The maximum principal stress is calculated in usr_upd.f, and stored in the user element variable USRE2(1), wherein USRE2(1) is defined as a global variable.

[0076] The damage prediction module is used to judge whether fracture occurs in the forging process and the position of the fracture, and specifically includes the following steps:

[0077] S8.1, when the damage module starts to calculate, judge whether the forging is deforming, that is, judge whether the strain rate is less than or equal to 0, when the strain rate is less than or equal to 0, end the damage calculation;

[0078] S8.2, when the damage module starts to calculate, judge whether the stress is less than 0, when the stress is less than 0, end the damage calculation, so as to judge whether the forging process is ended;

[0079] S8.3, when the damage module starts to calculate, if the strain rate is greater than 0 and the stress σ is greater than 0, start the damage calculation, and the damage value is calculated according to the ductile fracture criterion;

[0080] S8.4, when the calculation starts, the common variable unit node temperature TEMPE(8) is called by using the common statement, TEMPE(8) has 8 values, which are TEMPE(1), TEMPE(2), TEMPE(3), TEMPE(4), TEMPE(5), TEMPE(6), TEMPE(7), and TEMPE(8), the temperature used for calculating the damage value is the unit temperature T, which is obtained by solving the node temperature, and the related formula is:

[0081]

[0082] S8.5, after the temperature calculation is completed, the maximum principal stress calculation subroutine MAXPRN3 (STSE, PRNSTS, IFLAG, HY) is called using the call statement (maximum principal stress (stress, maximum principal stress, root criterion, hydrostatic stress)) to calculate the damage value according to the fracture criterion.

[0083] The ductile fracture criterion is:

[0084]

[0085] wherein ε f is the true strain at fracture, σ * is the maximum principal stress, is the equivalent stress, T is the temperature, is the strain rate, D is the damage factor, is the damping coefficient, which is a function of temperature and strain rate, m1 is the temperature influence factor on the damage factor, m2 is the strain rate influence factor on the damage fracture, and A and B are material coefficients;

[0086] S8.6, after the calculation is completed, the damage value DAMG is returned to the main program and stored in the data file;

[0087] S9, the pre-processing module is opened to load the calculation results obtained in the previous steps, the last step is selected, the simulation mode is set to heat transfer and deformation, and the process name is forging;

[0088] S10, the finite element models of the upper die and the lower die are imported, the material properties are defined as rigid bodies, and the temperatures of the upper and lower dies are set to 300°C;

[0089] S11, the relative positions of the upper and lower dies and the blank are adjusted according to the actual production process requirements, the upper die is set as the main die, the movement direction is along the negative direction of the Z axis, the speed is 100 mm / s, and other boundary conditions such as the contact mode are set;

[0090] S12, the total analysis step is set to 200 steps, the step length control mode is set to die movement distance 0.1 mm / step (0.1 mm / step), and the total analysis step is set according to the minimum distance between the upper and lower dies divided by 1 / 3 of the minimum edge length of the blank grid. The die moves 1 / 3 of the minimum edge length of the blank grid per step;

[0091] S13, click Database Generation, check the settings (Chek), and if prompted that the data can be generated, click Generate to generate the DB data file. Otherwise, change the settings according to the relevant prompts; after the data is generated, save and exit the pre-processing module;

[0092] S14, in the simulator (computational solution) module operation solution, then in the post-processing analysis module load solution result, analysis metal flow rule, damage condition, temperature change condition, can more accurately judge forming process rupture condition, the damage simulation simulation result of the embodiment is as shown in Figure 2 .

[0093] Embodiment 3

[0094] A kind of damage simulation simulation method based on deform of the application is through the secondary development file interface of deform, using the official regulation absoft Fortran v11.0 Software to generate DEF_SIM_64.exe file for secondary development, the secondary development interface of software itself provides temperature, strain, stress and other related parameters, but the parameter related to material needs to be calibrated after experiment oneself and directly write in the value when secondary development, program runs first call secondary development file to calculate damage value, then return damage value to main program, main program again saves the value to DB file, so that it is displayed in the form of cloud picture in post-processing, specifically further comprising the following steps:

[0095] S1, the stress-strain curve, fracture strain experimental data at different temperatures and tensile speeds of 7075 aluminum alloy are obtained by high temperature tensile test;

[0096] S2, the experimental data obtained by step S1 are used to establish a macro flow stress constitutive model arrhenius;Combined with the basic properties of the elastic parameters and thermal performance parameters of the material, a material library based on Deform is established;

[0097] The arrhenius constitutive model is:

[0098]

[0099] The strain rate (s -1 ), R is gas constant (KJ / mol), T is absolute temperature (K), Q is the activation energy in thermal deformation process (KJ / mol), σ is the flow stress value corresponding to the given strain value (MPa), A (s -21 ), α (MPa) and n are material constants that need to be measured in the experiment.

[0100] S3, design a damage prediction module for predicting the forging hot forming process, design a secondary development subprogram flowchart for damage prediction by using the finite element theory of metal plastic forming, establish a ductile fracture criterion model according to the data of the influence of temperature and strain rate on strain at fracture obtained in step S1, write a user subprogram by using Fortran language and the secondary development document DEF_SIM (user-defined calculation) provided by the Deform simulation software for secondary development, embed the Deform software for secondary development, so that the Deform software after secondary development can more accurately predict the influence of temperature and strain rate on fracture in the forging forming process;

[0101] The damage prediction module is used to judge whether fracture occurs in the forging process and the position of the fracture, and specifically comprises the following steps:

[0102] S3.1, when the damage module starts to calculate, judge whether the forging is deforming, that is, judge whether the strain rate is less than or equal to 0, when the strain rate is less than or equal to 0, end the damage calculation;

[0103] S3.2, when the damage module starts to calculate, judge whether the stress is less than 0, when the stress is less than 0, end the damage calculation, so as to judge whether the forging process is ended;

[0104] S3.3, when the damage module starts to calculate, if the strain rate is greater than 0 and the stress σ is greater than 0, start the damage calculation, and the damage value calculation is based on the ductile fracture criterion;

[0105] S3.4, when the calculation starts, call the common variable unit node temperature TEMPE (8) through the common statement, TEMPE (8) has 8 values, which are TEMPE (1), TEMPE (2), TEMPE (3), TEMPE (4), TEMPE (5), TEMPE (6), TEMPE (7), and TEMPE (8), the temperature used for calculating the damage value is the unit temperature T, which is obtained by solving the node temperature, and the related formula is:

[0106]

[0107] S3.5, after the temperature calculation is completed, use the call statement to call the maximum principal stress calculation subprogram MAXPRN3 (STSE, PRNSTS, IFLAG, HY) (maximum principal stress (stress, maximum principal stress, root criterion, hydrostatic stress)), calculate the damage value according to the fracture criterion.

[0108] The ductile fracture criterion is:

[0109]

[0110] Wherein, εf true strain at fracture, σ * maximum principal stress, equivalent stress, T is temperature, strain rate, D is damage factor, damping coefficient, m1 is a temperature influence factor on damage factor, m2 is a strain rate influence factor on damage fracture, A and B are material coefficients;

[0111] S3.6 returns the damage value DAMG to the main program after the calculation is completed, and stores it in a data file;

[0112] S4, according to the size of the material, the forming process, a finite element model of simulation is established, including the upper die, the lower die and the blank;

[0113] S5, open the Deform pre-processing module, select SI standard as the unit, the name of this stage is compress (compression), import the finite element model of the blank, the upper die and the lower die, set the simulation mode to heat transfer, deformation, and the heat dissipation mode to free heat dissipation; set the contact condition, select the cylindrical surface and air contact according to the actual compression condition, the two sections and the die contact, set the material properties of the blank, the heat dissipation coefficient, the constitutive model arrhenius, the fracture criterion; divide the blank into meshes, define the initial temperature of the blank;

[0114] S6, adjust the relative position of the upper die, the lower die and the blank according to the actual production process requirements, set the upper die as the main die, the movement direction as along the negative direction of Z axis, the speed as 100 mm / s and the contact mode as other boundary conditions;

[0115] S7, set the total analysis step to 300 steps, the step length control mode to the die moving distance 0.1 mm / step (0.1 mm / step), and the total analysis step according to the minimum distance between the upper die and the lower die divided by 1 / 3 of the minimum edge length of the blank mesh, the die moving distance per step is 1 / 3 of the minimum edge length of the blank mesh;

[0116] S8, click Database Generation, check the settings (Chek), and if prompted that the data can be generated, click Generate to generate the DB data file, otherwise change the settings according to the relevant prompts; after generating the data, save and exit the pre-processing module;

[0117] S9, operate and solve in the simulator (calculation solving) module, then load the solving results in the post-processing analysis module, analyze the metal flow rule, damage condition and temperature change condition, so as to more accurately judge the rupture condition in the forming process, the damage simulation and simulation results of the embodiment are shown in Figure 3 .

[0118] The preferred embodiments of the application disclosed above are only to facilitate the elucidation of the application. The preferred embodiments do not describe all the details of the application and limit the application to the specific embodiments described. Obviously, many modifications and variations can be made in light of the teachings above. The description is chosen and described in order to best explain the principles of the application and its practical application to thereby enable others skilled in the art to best utilize the application and get the best results from the application. The application is only limited by the claims and their full scope and equivalents.

Claims

1. A method for damage simulation based on deform, characterized in that, It comprises the following steps: A macroscopic flow stress constitutive model is established according to the experimental data of stress-strain curves, fracture strain under different temperatures and stretching speeds; A material library based on Deform is established in combination with the basic properties of the material, including elastic parameters and thermal performance parameters; A ductile fracture criterion model is established according to the obtained data of the influence of temperature and strain rate on strain at fracture, a damage prediction module for predicting the hot forming process of forging is established, and whether fracture occurs in the forging process is predicted; The ductile fracture criterion model is: where ε f is the true strain at break, σ * is the maximum principal stress, is the equivalent stress, T is the temperature, is the strain rate, denotes the equivalent strain, D is the damage factor, is a function of the temperature T and the strain rate , m1 is an influence factor of the temperature on the damage factor, m2 is an influence factor of the strain rate on the damage at break, A, B are material coefficients.

2. The deform-based damage simulation method of claim 1, wherein, The damage prediction module is used to judge whether fracture occurs in the forging process and the fracture position, and specifically comprises: It is judged whether the forging is deforming, i.e., whether the strain rate is less than or equal to 0, and when the strain rate is less than or equal to 0, the damage calculation is ended; When the damage module starts to calculate, it is judged whether the stress is less than 0, and when the stress is less than 0, the damage calculation is ended to judge whether the forging process is ended; When the damage module starts to calculate, if the strain rate is greater than 0 and the stress σ is greater than 0, the damage calculation is started and the damage value is calculated according to the ductile fracture criterion; After the calculation is completed, the damage value DAMG is returned to the main program and stored in a data file; A finite element model for simulation is established according to the size of the material, the forming process, The finite element model is imported into the Deform pre-processing module for assembly, and process parameters are set, including material type, simulation type, mesh division, constitutive model, fracture criterion, yield criterion, temperature, movement direction, and after the setting is completed, a DB file is generated and saved; In the simulator module, the solution is calculated, and in the post-processing analysis module, the solution result is loaded to analyze the metal flow rule, damage condition and temperature change.

3. The deform-based damage simulation method of claim 1, wherein, The basic properties include material constitutive model parameters, fracture criterion parameters, simulation control process parameters, mold movement speed and direction, assembly relationship, mesh division quantity, and related parameters of the initial temperature of the material.

4. The deform-based damage simulation method of claim 1, wherein, When setting the parameters, the part about the damage and fracture criterion needs to select the number corresponding to the developed model.

5. The deform-based damage simulation method of claim 2, wherein, The temperature for calculating the damage value is the temperature of the integral point, and the integral point temperature is obtained by using the node temperature.

6. The deform-based damage simulation method of claim 5, wherein, The integral point temperature is denoted as T. TEMPE1, TEMPE2, TEMPE3, TEMPE4, TEMPE5, TEMPE6, TEMPE7, TEMPE8 represent 8 values of the node temperature referenced by the public variable using the public region command.

7. A method of damage simulation based on deform according to any one of claims 1 to 6, characterized in that, The constitutive model is: wherein is the strain rate, R is the gas constant, T is the absolute temperature, Q is the activation energy during hot deformation, σ is the corresponding flow stress value at a given strain value, and A, a and n are all material constants to be determined experimentally.

8. The deform-based damage simulation method of claim 7, wherein, Before predicting the model, a finite element model for simulation is established according to the size of the material, the forming process, the model is meshed, and the initial temperature of the model is defined.

9. The deform-based damage simulation method of claim 8, wherein, The simulation mode is set as heat transfer, and the heat dissipation mode is free heat dissipation.

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