A method for constructing an impact simulation test based on digimat / abaqus

Abstract

The application provides a kind of impact simulation test construction method based on Digimat / Abaqus, comprising: the setting of the impact finite element model of stab-resistant material, including geometric model, material model, contact definition, load and boundary condition and the output setting of stab-resistant impact simulation result and analysis model, including stab-resistant impact simulation result and stab-resistant impact model verification.The material model containing fabric composite material microstructure information constructed by the application using Digimat can be directly used as the material attribute input of Abaqus / CAE impact finite element model for calculation through Digimat to Abaqus interface technology, realizing the multi-scale analysis of composite material microstructure parameters and macroscopic impact load condition response;And combined with the physical test of stab-resistant impact, the effectiveness of the equivalent impact finite element model of the impact model of the stab-resistant material on the backing is established and verified.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of functional composite materials, and particularly relates to a construction method of an impact simulation test based on Digimat / Abaqus. BACKGROUND

[0002] With the increasing application of fabric structure composites, the research on the impact performance of fabric structure composites in the fields of automobiles, aerospace, sports, safety protection and the like is particularly urgent. However, the mechanical property research and optimization design process of the material are time-consuming and material-consuming, and the test process cannot be fully analyzed. Seeking a method capable of reflecting the relationship between the mechanical properties and the microscopic structure parameters of the fabric reinforced composite material and the external load impact can provide a basis for developing textile composite materials for human protection. SUMMARY

[0003] Therefore, the present application provides a construction method of an impact simulation test based on Digimat / Abaqus, which can reflect the relationship between the mechanical properties and the microscopic structure parameters of the fabric reinforced composite material and the external load impact, and the specific scheme is as follows.

[0004] A construction method of an impact simulation test based on Digimat / Abaqus, comprising the following steps.

[0005] Firstly, an Abaqus / CAE is used to establish a geometric model of an impact object and an impacted object, and the impacted object comprises a to-be-tested anti-stab material and a backing material.

[0006] Secondly, a material model of the impact object and the impacted object is constructed, wherein the material model of the to-be-tested anti-stab material is constructed by using Digimat.

[0007] Then, the to-be-tested anti-stab material and the backing material in the model and the contact interaction between the impact object and the to-be-tested anti-stab material are defined in Abaqus.

[0008] Finally, the material model is called by the impact geometric model to perform simulation experiment analysis, and the external load impact performance of the to-be-tested anti-stab material is judged.

[0009] Preferably, the geometric model of the impact object and the impacted object is constructed by using Abaqus / CAE direct modeling, and the specific modeling method comprises the following steps.

[0010] The specific modeling method comprises the following steps.

[0011] 1) Geometric model and mesh division of a test impact cutter;

[0012] 2) Geometric model and mesh division of the backing material;

[0013] 3) the geometric model of the anti-stab material and meshing.

[0014] Preferably, the geometric model of the impact knife is established according to the standard required size of the anti-stab clothing, and the modeling step of the geometric model of the impact knife is:

[0015] 1) the geometric model of the knife is constructed by entity stretching, and a deformation body component is created first, and then rigid body constraints are applied to the knife;

[0016] 2) the point mass of the knife is added by attribute setting in Abaqus;

[0017] 3) the knife is segmented in the Part module according to the meshing method, and the geometric model of the knife is meshed by C3D4 unit.

[0018] Preferably, the geometric model of the backing material and the meshing method are:

[0019] 1) the geometric model of the backing material is established according to the standard required size in the reference anti-stab clothing for police;

[0020] 2) the geometric body of the backing material is created by entity stretching;

[0021] 3) the geometric body is segmented in the Part module according to different components of the backing material;

[0022] 4) the geometric model of the backing material is meshed by hexahedron unit.

[0023] Preferably, the geometric model of the anti-stab material and meshing includes the following steps:

[0024] 1) the geometric model of the anti-stab material is created by entity stretching;

[0025] 2) the geometric model is segmented according to the environment set by physical test;

[0026] 3) the model is meshed by hexahedron unit.

[0027] Preferably, the material model includes the anti-stab material, the impact knife and the backing material,

[0028] the properties of the anti-stab material are constructed by Digimat;

[0029] the properties of the impact knife and the backing material are set by Abaqus material model, and the backing material is used to simulate human tissue;

[0030] the modeling step of the material model includes:

[0031] 1) the single-layer composite material model is constructed by Digimat;

[0032] 2) Abaqus can directly call the material model containing the plain fabric microstructure characteristics in the single-layer composite material model built by the Digimat material model through the plug-in interface to perform calculation;

[0033] 3) Generate a data file and related settings for the material model Digimat-CAE / Abaqus coupling analysis.

[0034] Preferably, the contact definition refers to the definition of the interaction of the two contacts of the stab-resistant material and the backing material model in Abaqus, specifically:

[0035] First, the surface-to-surface contact method is used to define the contact surface between the stab-resistant material and the backing material in the material model, and the tangential friction coefficient is set to simulate the general contact friction state between the two components;

[0036] Second, the general contact method is used to define the contact between the tool and the internal surface set of the stab-resistant material during the stabbing process.

[0037] Preferably, the method for setting the load and boundary conditions is:

[0038] 1) Place the tool at a position 0.01mm away from the surface of the stab-resistant clothing;

[0039] 2) Assign the tool an initial speed of 4472mm / s through the pre-defined field method to achieve instantaneous impact motion simulation;

[0040] 3) Define the complete constraint of the bottom edge of the backing material in three directions, and the constraint of the tool in the X and Z directions;

[0041] 4) Define the output settings, which include field variable result output and history variable output result.

[0042] Preferably, the stab impact simulation result includes the material properties of the Digimat material model with microstructure feature information defining the stab-resistant material model in Abaqus,

[0043] The piercing process of the stab-resistant impact finite element model includes the initial contact of the impact tool with the surface of the stab-resistant material, the gradual penetration of the tool tip into the stab-resistant material, the maximum penetration depth of the tool tip, and the gradual rebound of the impact tool.

[0044] Preferably, the stab impact model verification includes the energy change curve of the stab-resistant impact model created by the visualization module, the displacement, velocity and acceleration curves of the tool of the stab-resistant impact finite element model with time.

[0045] Compared with the prior art, the application has the beneficial effects that:

[0046] The material model containing the fabric composite microstructure information constructed by the Digimat is used, the material attribute input of the Abaqus / CAE impact finite element model can be directly calculated through the Digimat to Abaqus interface technology, the multi-scale analysis of the composite microstructure parameters and the response under the macro-impact load condition is realized; and the effectiveness of the equivalent impact finite element model of the impact model of the stab-resistant material on the backing is established and verified respectively by combining the stab-resistant impact physical test, so as to provide a research basis for more deeply and systematically studying the macro-micro mechanical properties of the stab-resistant material under the impact test condition of the external load and the mutual influence.

[0047] The technical solutions of the present application are described in further detail below by means of the drawings and embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0048] The accompanying drawings are included to provide a further understanding of the present application, and constitute a part of the specification, and are used to explain the present application together with the embodiments of the present application, and do not constitute a limitation on the present application. In the drawings:

[0049] Figure 1 It is a geometric model of an impact knife in the impact simulation test construction method based on Digimat / Abaqus in the embodiments of the present application;

[0050] Figure 2 It is a backing material geometric model in the impact simulation test construction method based on Digimat / Abaqus in the embodiments of the present application;

[0051] Figure 3 It is a backing material structure diagram in the impact simulation test construction method based on Digimat / Abaqus in the embodiments of the present application;

[0052] Figure 4 It is a stab-resistant material geometric model in the impact simulation test construction method based on Digimat / Abaqus in the embodiments of the present application;

[0053] Figure 5 It is a network division of the stab-resistant material impact finite element model in the impact simulation test construction method based on Digimat / Abaqus in the embodiments of the present application;

[0054] Figure 6 It is a surface-to-surface contact definition diagram of the stab-resistant material and the backing material in the impact simulation test construction method based on Digimat / Abaqus in the embodiments of the present application;

[0055] Figure 7A general contact definition diagram between a tool and an internal surface set of a stab-resistant material in a kind of impact simulation test construction method based on Digimat / Abaqus in the embodiment of the application;

[0056] Figure 8 A load boundary condition setting diagram in a kind of impact simulation test construction method based on Digimat / Abaqus in the embodiment of the application;

[0057] Figure 9 A stab-resistant material impact analysis model energy change curve chart in a kind of impact simulation test construction method based on Digimat / Abaqus in the embodiment of the application;

[0058] Figure 10 A curve chart of displacement, velocity and acceleration of impact tool with time in a kind of impact simulation test construction method based on Digimat / Abaqus in the embodiment of the application;

[0059] Figure 11 A tool structure diagram for impact test in a kind of impact simulation test construction method based on Digimat / Abaqus in the embodiment of the application. DETAILED DESCRIPTION

[0060] The preferred embodiments of the application will be described in detail below with reference to the accompanying drawings, and it should be understood that the preferred embodiments described herein are only used to illustrate and explain the application, and are not used to limit the application.

[0061] The application will now be described in detail by the following examples

[0062] The stab-resistant material impact finite element model established by the stab-resistant clothing impact finite element model in the embodiment mainly is according to the test requirement of the impact on the backing material specified in the standard of police stab-resistant clothing;

[0063] According to the attached Figures 1-11 The impact simulation test construction method based on Digimat / Abaqus shown in the figure, it includes:

[0064] Firstly, the geometric model of impact object and impacted object is established by Abaqus / CAE, and the impacted object includes the stab-resistant material to be tested and the backing material;

[0065] Secondly, the material model of impact object and impacted object is constructed, wherein the material model of the stab-resistant material to be tested is constructed by Digimat;

[0066] Then, the two kinds of contact interactions of the stab-resistant material to be tested and the backing material, the impact object and the stab-resistant material to be tested in the model are defined in Abaqus;

[0067] Finally, the material model is called through the impact geometry model to conduct simulation experiments and analyze the external load impact performance of the stab-resistant material to be tested.

[0068] It should be noted that the finite element model of stab-resistant material impact in this application, including the geometric model, material model, contact definition, load and boundary condition settings, and output settings, is used to explore the effectiveness of the impact finite element model based on the multi-scale co-simulation method.

[0069] The simulation results and analysis model for stab-resistant impact, including simulation results and model verification, are used to verify the feasibility of the Digimat to Abaqus co-simulation method and the effectiveness of the finite element model of stab-resistant material impact.

[0070] Furthermore, the geometric models of the impact object and the impacted object are constructed using direct modeling with Abaqus / CAE. The specific modeling method includes the following steps:

[0071] 1) Geometric model and mesh generation of the impact tool used in the experiment;

[0072] 2) Geometric model and mesh generation of the backing material;

[0073] 3) Geometric model and mesh generation of stab-resistant material.

[0074] The geometric model mainly refers to the puncture geometric model. The backing material and stab-resistant material in the geometric model are both regular cuboids. The impact tool is a standard cutting part. The geometric model of the tool is established according to the dimensional requirements of police stab-resistant vest standards. In this invention, the geometric model of the impact tool is established according to the dimensional requirements of stab-resistant vest standards. A schematic diagram of the geometric structure of the impact tool used in this embodiment is shown below. Figures 1-1 As shown.

[0075] Furthermore, the modeling steps for the geometric model of the impact tool are as follows:

[0076] 1) Construct the tool geometry model by solid extrusion, first create deformable parts, and then apply rigid body constraints to the tool;

[0077] 2) Add tool point quality in Abaqus through property settings;

[0078] 3) The tool is first divided in the Part module according to the meshing method. The tool geometry model is meshed using C3D4 elements, generating a total of 5439 elements.

[0079] In order to ensure that the impact energy of the impact tool tip reaching the stab-resistant surface in this embodiment is consistent with the 24J impact energy generated by the total mass of the tool and the falling body in the physical test, a tool point mass of 2.4KG is added through attribute setting in Abaqus. Since the impact tool in this embodiment is an irregular geometry, the contact action of the tool tip on the stab-resistant material is critical during the impact process. Therefore, the tool needs to be segmented in the Part module according to the meshing method, and the created impact tool geometry model and segmentation are as shown in Figure 11 .

[0080] Further, the backing material geometry model and meshing method are:

[0081] 1) The backing material geometry model is established according to the standard required size in the reference police stab-resistant clothing;

[0082] 2) The geometry of the backing material is created by the method of entity stretching;

[0083] 3) The geometry is segmented in the Part module according to different components of the backing material;

[0084] 4) The backing material geometry model is meshed with hexahedral elements, generating a total of 44500 elements.

[0085] The backing material geometry model is created with a size of 400mm×400mm×67mm according to the standard required size in the reference police stab-resistant clothing, wherein the composition of the backing material is as shown in Figure 3 , including 4 layers of 6mm thick neoprene sponge, 1 layer of 30mm thick foam plastic, and 2 layers of 6.5mm thick natural rubber from the impact contact surface downward, and the created backing material geometry model and its segmentation are as shown in Figure 2 .

[0086] Further, the stab-resistant material geometry model and meshing method as shown in Figure 5 include the following steps:

[0087] 1) Create a stab-resistant material geometry model by entity stretching;

[0088] 2) Segment the geometry model according to the physical test setting environment

[0089] 3) Mesh the model with hexahedral elements, generating a total of 165362 elements.

[0090] The stab-resistant material used in this embodiment is a 24-layer aramid resin laminated composite material, and its thickness is measured to be 9.6mm. Therefore, the size of the constructed stab-resistant material geometry model is 250mm×250mm×9.6mm. The stab-resistant material geometry model is segmented according to the physical test setting environment as shown inFigure 4 as shown.

[0091] In the present application, the material model comprises a stab-resistant material, an impact knife and a backing material,

[0092] The properties of the stab-resistant material are constructed by Digimat;

[0093] The properties of the impact knife and the backing material are set by using the Abaqus material model, and the backing material is used to simulate human tissue;

[0094] The modeling step of the material model comprises:

[0095] 1) constructing a single-layer composite material model by Digimat;

[0096] 2) Abaqus can directly call the material model containing the plain weave fabric microstructure characteristics in the single-layer composite material model constructed by the Digimat material model for calculation;

[0097] 3) generating a data file and related settings for material model Digimat-CAE / Abaqus coupling analysis,

[0098] The step of the data file and related settings is: first, define the analysis in Digimat-CAE and generate the interface file; then define the Digimat user material in Abaqus;

[0099] The Abaqus calls the Digimat material model constructed by the above interface file, and at the same time, the element deletion must be defined when Abaqus / Explicit calls the Digimat material model.

[0100] It should be noted that the stab-resistant impact finite element model in the present embodiment is according to the requirements of the police stab-resistant standard, the impact knife material for testing is steel, and the setting parameters of the properties of the backing material are as shown in Table 1:

[0101] Table 1 Impact knife and backing material parameter definition

[0102]

[0103] In the present embodiment, the single-layer aramid resin composite material model constructed by Digimat, Abaqus can directly call this material model containing the plain weave fabric microstructure characteristics for calculation through the plug-in interface. Among them, the data file and related settings for material model Digimat-CAE / Abaqus coupling analysis need to be generated.

[0104] Wherein, Digimat.daf input file is established in Digimat-CAE, and Abaqus / Explicit is selected in analysis type. Clicking run analysis, the following three interface files are generated: Digimat material file in *.mat format, which is used for main input file of structure finite element analysis later; *.aba file, which contains information definition related to Abaqus user profile, and is copied to Abaqus input area later; *.log file, which contains running information, including error message of running failure and the like;

[0105] Relevant coupling analysis of Digimat to Abaqus is carried out in Abaqus *.inp file through the following command line.

[0106] Material name is specified through the following command line, which is used for calling *.mat Digimat material file in Abaqus model. And.mat and.aba files and.daf files belonging to Digimat GUI are placed in Abaqus working directory.

[0107] *Material, name=Digimat material name

[0108] The number of state variables is specified through the following command:

[0109] *Depvar 81

[0111] SDV is not defined in Abaqus, but is simply numbered. The number of Depvar is determined according to the user-defined Digimat material model, and corresponds to the number of SDV in ODB, and the SDV is described in.aba file in advance, which can avoid renaming after Abaqus finite element model analysis.

[0112] The material is user-defined through the following command:

[0113] *User Material, constants=1 0

[0115] The constant only indicates that the behavior of the material will be called by Digimat material library Digimat-CAE / Abaqus through VUMAT interface instead of directly by Abaqus material modeling. Generally, the value is 0.

[0116] The interface file generated above can be called by Abaqus to build the Digimat material model. In addition, unit deletion must be defined for Abaqus / Explicit calling Digimat material model.

[0117] In the present application, the contact definition refers to the definition of the interaction of two contacts of the anti-stab material and the backing material model in Abaqus, specifically:

[0118] Firstly, the contact surface of the anti-stab material and the backing material in the material model is defined by using the face-to-face contact method, and the tangential friction coefficient is set to simulate the general contact friction state between the two components;

[0119] Secondly, the contact between the tool and the internal surface set of the anti-stab material during the stabbing process is defined by using the general contact method.

[0120] In the present embodiment, according to the fact that the anti-stab material and the backing material are in contact during the test process, the tool is gradually contacted with each layer of anti-stab material from the outer surface of the tool after free fall. Therefore, two contact interaction definitions need to be defined in Abaqus. Firstly, the contact surface of the anti-stab material and the backing material is defined by using the face-to-face contact method, and the tangential friction coefficient of 0.3 is set to simulate the general contact friction state between the two components, as shown in Figure 6 Secondly, the contact between the tool and the internal surface set of the anti-stab material during the stabbing process is defined by using the general contact method, as shown in Figure 7 .

[0121] Further, the method for setting the load and boundary conditions is:

[0122] 1) The tool is placed at a position 0.01 mm away from the surface of the anti-stab garment;

[0123] 2) The tool is assigned an initial speed of 4472 mm / s by using the pre-defined field method, so as to realize the simulation of instantaneous impact motion;

[0124] 3) The complete constraint of the backing material bottom edge in three directions and the constraint of the tool in X and Z directions are defined;

[0125] 4) The output setting is defined, which includes the field variable result output and the history variable output result.

[0126] In the embodiment, the impact test of the stab-resistant material on the backing mainly controls the height of the free fall of the knife, so as to generate a certain impact energy by the free fall movement of the knife and the counterweight. In Abaqus, the simulation can be realized by defining the initial velocity as zero and only applying the gravitational acceleration. However, according to the analysis of the physical test results, it can be known that one impact test is completed in about 0.01 s, and it only takes about 0.007 s from the beginning of the contact between the tip of the knife and the stab-resistant material to the penetration and reaching the maximum impact force value, which is completely a transient movement. Therefore, a more efficient method is adopted in the embodiment, that is, the knife is placed at a position of 0.01 mm above the surface of the stab-resistant clothing, and the initial velocity of the knife is defined as 4472 mm / s by a pre-defined field, so as to realize the simulation of the instantaneous impact movement, as shown in FIG. 6. Figure 8

[0127] In the embodiment, the output setting of Abaqus can define two kinds of outputs, wherein the frequency of the field variable result output is relatively low, because the result is usually for the whole model or the result output of the model containing most of the model. The output of the stress and displacement field is usually set in this way. The output result frequency of the history variable is relatively high, and is mainly used for the variable output of the local model. In this paper, the displacement, velocity and acceleration of the tip of the knife are output by using the output mode, and the result can be generated in the visualization function module to generate an XY graph for viewing.

[0128] In addition, by using the following commands in the Abaqus.inp file, Abaqus stores the SDV in the ODB file, so that the material definition of Digimat can be read in the Abaqus output.

[0129] *Element output

[0130] SDV.

[0131] Further, the stab impact simulation result includes the material model of the microstructure feature information of Digimat, the material properties of the stab-resistant material model defined in Abaqus, so as to perform the calculation and analysis of the finite element model under the impact load.

[0132] The penetration process of the stab-resistant material impact finite element model includes the moment when the impact knife just contacts the surface of the stab-resistant material, the moment when the tip of the knife gradually penetrates into the stab-resistant material, the moment when the tip of the knife reaches the maximum penetration depth, and the moment when the impact knife gradually rebounds.

[0133] In the embodiment, the stab impact model verification includes the energy change curve of the stab-resistant material impact model created by the visualization module, the displacement, velocity and acceleration curves of the knife of the stab-resistant material impact finite element model with time.

[0134] ​The impact finite element model of the anti-stabbing material constructed in this embodiment is mainly to verify the feasibility of the Digimat to Abaqus joint simulation method. That is, the material properties of the anti-stabbing material model can be defined in Abaqus by using the Digimat material model containing the microstructure feature information, so as to perform the calculation and analysis of the finite element model under the impact load. The piercing process of the anti-stabbing material impact finite element model is shown in FIG. 8. Figure 2-1

[0135] The process of the tool piercing into the anti-stabbing material can be analyzed by the anti-stabbing material impact finite element model. Figure 2-1 The anti-stabbing material impact finite element model is gradually pierced into the anti-stabbing material from the moment when the impact tool contacts the surface of the anti-stabbing material, and the force of the anti-stabbing area contacting the tool tip gradually increases, and reaches the maximum impact force when the tool tip penetrates to the state of FIG. (c). Due to the protection of the anti-stabbing material and the buffering effect of the backing material to a certain extent, the impact tool begins to rebound, and the impact process is completed at the state of (e).

[0136] Figure 9 The energy change curve of the anti-stabbing material impact model created by the Abaqus visualization module is shown in FIG. 9. The overall energy of the anti-stabbing material impact model is maintained at about 24J, and when the impact tool pierces into the anti-stabbing garment, the kinetic energy of the impact model begins to decrease, and the internal energy begins to increase, and a part of the energy is converted into friction dissipation energy. As can be seen from the figure, the kinetic energy of the impact model is the smallest at the time of 0.008s. The tool tip starts to pierce into the anti-stabbing material from 0s to reach the maximum impact force within 0.0079s. Subsequently, due to the protection of the multi-layer anti-stabbing material and the buffering effect of the backing material, the tool begins to rebound to complete the impact motion.

[0137] Figure 10 The displacement, velocity and acceleration curves of the tool of the anti-stabbing material impact finite element model with time are shown in FIG. 10. The acceleration curve of the impact tool with time is basically consistent with the acceleration curve with time collected by the physical test. At this stage, the reaction force of the anti-stabbing material on the falling body is less than the weight of the falling body, so the speed of the tool increases. When the maximum impact force is reached, that is, the tool tip pierces to the deepest, and the measured piercing depth is 7.6mm, the speed of the tool changes little and tends to zero because the reaction force of the anti-stabbing material on the falling body is close to the weight of the falling body.

[0138] According to the above analysis, the calculation results of the anti-stabbing material impact model are basically consistent with the anti-stabbing material impact test results on the backing, which verifies the effectiveness of the anti-stabbing material impact finite element model.

[0139] ​The equivalent impact simulation model of the anti-piercing clothes constructed by the present application can verify and analyze the anti-piercing impact test on the human body; secondly, the simulation model constructed by the present application has a material model capable of reflecting the microstructure of the fabric reinforced composite material, and can be coupled with the structural finite element software to realize the verification analysis of the external load impact test under the macro condition; meanwhile, the material model can be modified, and then coupled with the equivalent impact finite element model of the anti-piercing clothes to perform the coupling calculation, which can be used for the macro-micro multi-scale analysis of the anti-piercing material, and provides a new research method for developing the textile composite material for human body protection.

[0140] Obviously, those skilled in the art can make various modifications and variations to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application belong to the scope of the claims of the present application and the equivalent technologies thereof, the present application also intends to include these modifications and variations.

Claims

1. A method for constructing an impact simulation test based on Digimat / Abaqus, characterized in that, The application relates to a method for simulating the impact performance of a stab-resistant material, and belongs to the technical field of stab-resistant material simulation. Firstly, an Abaqus / CAE is adopted to establish the geometric models of an impact object and a struck object, wherein the struck object comprises a stab-resistant material to be tested and a backing material; Secondly, material models of the impact object and the struck object are constructed, wherein the material model of the stab-resistant material to be tested is constructed by adopting Digimat; Then, the two contact interactions of the stab-resistant material to be tested and the backing material in the model and the contact interaction of the impact object and the stab-resistant material to be tested are defined in Abaqus; Finally, the material model is called by the impact geometric model to perform simulation experiment analysis, so as to judge the external load impact performance of the stab-resistant material to be tested; The material model comprises a stab-resistant material, an impact knife and a backing material, The attribute setting of the impact knife and the backing material adopts an Abaqus material model, and the backing material is used for simulating human tissues; The modeling step of the material model comprises the following steps: 1) a single-layer composite material model is constructed by adopting Digimat, 2) Abaqus can directly call the material model in the single-layer composite material model constructed by the Digimat material model and comprising the planar fabric microstructure characteristics to perform calculation; Data files and related settings for the material model Digimat-CAE / Abaqus coupling analysis are generated; The contact definition refers to the definition of the two contact interactions of the stab-resistant material and the backing material model in Abaqus, and the specific definition comprises the following steps: Firstly, a surface-to-surface contact mode is adopted to define the contact surface of the stab-resistant material and the backing material in the material model, and a tangential friction coefficient is set to simulate the general contact friction state between the two components; Secondly, a general contact mode is adopted to define the contact between the knife and the internal surface set of the stab-resistant material in the stabbing process; The method for setting the load and boundary conditions comprises the following steps: 1) the knife is placed on the surface of the stab-resistant clothing; 2) the initial speed of the knife is specified by adopting a pre-defined field mode, so as to realize the simulation of the instantaneous impact motion; 3) the complete constraint of the bottom edge of the backing material in three directions and the constraint of the knife in the X and Z directions are defined; 2. The method of claim 1, wherein, 4) output settings are defined, and the output settings comprise field variable result output and history variable output result. The geometric models of the impact object and the struck object are directly modeled by adopting Abaqus / CAE, and the specific modeling method comprises the following steps: 1) a geometric model and a mesh division of a test impact object, wherein the impact object is an impact knife; 2) a geometric model and a mesh division of a backing material; 3. The method of claim 2, wherein, 3) a geometric model and a mesh division of a stab-resistant material. The geometric model of the impact knife is established according to the size required by a stab-resistant clothing standard, and the modeling steps of the geometric model of the impact knife comprise the following steps: 1) the geometric model of the knife is constructed by adopting a solid stretching mode, and a deformation body component is first created, and then a rigid body constraint is applied to the knife; 2) the point mass of the knife is added by adopting attribute setting in Abaqus; 4. The method of claim 2, wherein, 3) the knife is segmented in the Part module according to a mesh division method, and the geometric model of the knife adopts C3D4 unit mesh division. The geometric model and the mesh division method of the backing material comprise the following steps: 1) Establish the backing material geometry model according to the standard required size in the police anti-stab clothing; 2) Create the backing material geometry by the method of entity stretching; 3) Segment the geometry according to different components of the backing material in the Part module; 4) Divide the mesh of the backing material geometry model by hexahedron element.

5. The method of claim 2, wherein, The anti-stab material geometry model and mesh division include the following steps: 1) Create the anti-stab material geometry model by entity stretching; 2) Segment the geometry according to the physical test setting environment; 3) Divide the mesh of the model by hexahedron element.

6. The method of claim 1, wherein, The anti-stab impact simulation result includes the material model of the Digimat material model with the microstructure characteristic information to define the material attribute of the anti-stab material model in Abaqus, The piercing process of the anti-stab material impact finite element model includes the rigid contact of the impact cutter with the surface of the anti-stab material, the gradual piercing of the cutter tip into the anti-stab material, the maximum piercing depth of the cutter tip, and the gradual rebound of the impact cutter.

7. The method of claim 1, wherein, The anti-stab impact model verification includes the energy change curve of the anti-stab material impact model created by the visualization module, the displacement, velocity and acceleration change curves of the cutter of the anti-stab material impact finite element model with time.

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