Foaming material dynamic compression performance simulation method and system

Abstract

The invention relates to the technical field of material performance simulation, and discloses a foam material dynamic compression performance simulation method and system. The simulation method is applied to simulation equipment and specifically comprises the following steps: S101, determining a component proportionality coefficient of a to-be-tested foaming material, determining a repeating unit of the foaming material according to the component proportionality coefficient, constructing a polymer single-chain structure, and constructing a polyurethane amorphous unit cell initial model based on polymer single-chain structure interlinking; and S102, performing static compression on the polyurethane amorphous unit cell initial model by using a tensile universal testing machine, establishing a three-dimensional Voronoi finite element model of the polyurethane amorphous unit cell initial model, and setting the size of the three-dimensional Voronoi finite element model to be the same as the size of a test piece used in the test. Compared with important parameters such as yield strength, platform stress and densification strain obtained through tests, the accuracy of the simulation model is verified, and a solid foundation is laid for follow-up wider and more detailed research on the foamed aluminum material.

Description

Technical Field

[0001] The present invention relates to the technical field of material performance simulation, and in particular to a method and system for simulating dynamic compression performance of a foaming material. Background Art

[0002] Foam materials are a class of lightweight materials with a porous structure that contains a large number of gas-filled voids or bubbles. These materials are widely used in many fields, such as packaging, construction, automobile manufacturing, aerospace, etc., due to their unique physical and mechanical properties. The main characteristics of foam materials include low density, good thermal and sound insulation, excellent energy absorption and buffering capabilities, and relatively low cost.

[0003] An important advantage of foamed materials is that they can effectively absorb and disperse energy during dynamic compression. When the material is impacted, it undergoes a process of elastic deformation, plastic yielding, and final destruction, during which a large amount of energy is consumed through the folding and collapse of the bubble walls and gas compression. Therefore, foamed materials are often used as cushions, packaging materials, or car bumpers, etc., which require good energy absorption properties.

[0004] In order to better study and utilize foam materials, it is necessary to simulate the performance of foam materials. However, the existing dynamic compression performance simulation method cannot verify the feasibility and accuracy of the simulation during simulation. In addition, the existing dynamic compression performance simulation is not practical and has no promotion value. Summary of the invention

[0005] The purpose of the present invention is to provide a method and system for simulating the dynamic compression performance of foam materials, which has the advantages of high reliability and practicality, and solves the problems raised in the above-mentioned background technology.

[0006] The present invention is implemented as follows: a method for simulating dynamic compression performance of a foam material, applied to a simulation device, specifically comprising the following steps: S101: determining a component ratio coefficient of the foaming material to be tested, determining a repeating unit of the foaming material according to the component ratio coefficient, constructing a polymer single chain structure, and constructing an initial model of amorphous polyurethane crystal cells based on linking the polymer single chain structures; S102: using a tensile universal testing machine to statically compress the initial model of the polyurethane amorphous crystal cell, establishing a three-dimensional Voronoi finite element model of the initial model of the polyurethane amorphous crystal cell, and setting the size of the three-dimensional Voronoi finite element model to be the same as the size of the specimen used in the test; S103: performing a preliminary configuration screening on the three-dimensional Voronoi finite element model to be tested, performing simulation and solving using ABAQUS, and comparing the deformation of the static compression simulation with the test when the strain reaches the same value to verify the feasibility of the three-dimensional Voronoi model; S104: obtaining a screening unit cell model based on the three-dimensional Voronoi finite element model and optimizing the screened unit cell model, processing the optimized screened unit cell model based on a molecular dynamics method to obtain a final unit cell model to be tested; S105: Using MaterialsStudio software to analyze the final model of the unit cell to be tested, obtain its structural morphology, free volume and occupancy contour, use Hopkinson pressure bar equipment to perform dynamic impact test, and then use three-dimensional Voronoi model to perform dynamic compression simulation test, and finally obtain the dynamic compression performance parameter threshold of the foaming material.

[0007] Specifically, the three-dimensional Voronoi finite element model discretizes the continuum into multiple small units (elements), each of which is connected at nodes, and transmits forces and constraints through these nodes. It is mainly used for engineering analysis and predicts the response of structures or systems through numerical calculations. It is suitable for solving complex problems.

[0008] The three-dimensional Voronoi finite element model is a model established using the finite element analysis method. It is a group of units that are connected only at nodes, transmit forces at nodes, and are constrained at nodes. This model is mainly used for engineering analysis, such as structural analysis, thermal analysis, fluid analysis, etc., to help engineers predict and evaluate product performance; 3D solid models are created through computer-aided design (CAD) software to represent the 3D geometry and physical properties of an object. They are mainly used in product design, manufacturing, and simulation to help designers and engineers visualize and verify during product development. Specifically, ABAQUS's nonlinear analysis function has been widely recognized by high-end users in design and research. In terms of usage skills, ABAQUS's pre-processing and post-processing functions are equally excellent. Through precise meshing, material property settings, and result visualization, users can easily manage and analyze simulation data. In addition, solving non-convergence problems, optimizing meshing, or selecting appropriate solver settings are also key steps to improve analysis accuracy; The 3D Voronoi model is a geometric structure used to describe the distribution of point sets in space. It is used in materials science, geology, computer graphics and other fields. The 3D Voronoi model can be generated through specific plug-ins or software, such as the Voronoi3D plug-in generation interface in Abaqus. Users can choose to generate crystal models in the shape of a cuboid, cylinder or sphere as needed. They can also use the Voronoi class in the scipy.spatial library to generate a 3D Voronoi diagram, which is usually used to simulate foam structures, etc. Model characteristics: The characteristic of the 3D Voronoi model is that it divides the space into multiple regions, each region corresponds to a generation point, and the distance from any point in the region to the generation point is the minimum. This model can contain grid boundaries or not, depending on the user's needs and application scenarios; Preferably, in S101, determining the component ratio coefficient of the foaming material to be tested, determining the repeating unit of the foaming material according to the component ratio coefficient, and constructing a polymer single chain structure, including: Adding two-dimensional carbon / nitrogen / carbonitride material and high-temperature foaming agent to polyether alcohol successively to fully react, cooling and adding glycidyl ether curing agent to obtain uniform repeating units of polyether alcohol mixture foaming material; In a nitrogen-flushing environment, the repeating units of the thermoplastic polyether ester elastomer and the polyether alcohol mixture foaming material which have been dried are added into a reaction kettle and mixed evenly, and the copolymerized thermoplastic polyether ester elastomer polymer single chain structure is obtained by pressurized extrusion in a molten state.

[0009] Preferably, in S102, during the test, data is transmitted to a computer via a connected sensor to obtain a force-displacement curve of the compression of the foamed material under the experimental conditions. Since the test ultimately aims to obtain a stress-strain curve, the data needs to be calculated and processed.

[0010] Preferably, in S103, in view of the complexity of the three-dimensional Voronoi model itself, explicit dynamics is used to perform simulation solution calculation during simulation solution.

[0011] Preferably, in S103, by comparing the static compression stress-strain curve of the foamed material obtained by the experiment with the stress-strain curve obtained by simulation, it can be seen that the two have the same trend, and both have three typical compression processes: linear elastic deformation stage, plastic platform stage and densification stage, so that it can be concluded that the three-dimensional Voronoi model can effectively simulate the internal structure of the foamed material.

[0012] Preferably, in S104, in the static compression test, yield strength, platform stress and densification strain are important parameters.

[0013] Preferably, the yield strength is the stress corresponding to the end of the linear elastic stage and the beginning of the yield stage, the platform stress is the average stress from the beginning of entering the platform area to the end of the platform area, and the densification strain is the strain corresponding to the intersection of the straight line with the platform stress value and the tangent of the densification stage. The important parameters such as yield strength, platform stress and densification strain obtained by the experiment are compared to verify the accuracy of the simulation model.

[0014] Preferably, in S105, a Hopkinson pressure bar device with a diameter of 37.5 mm is used to carry out a dynamic impact test, the bullet length is 600 mm, the incident rod and the transmission rod are both 2000 mm long, the material is LC4 aluminum alloy, the cylindrical specimen has a diameter of 30 mm and a height of 20 mm, the impact velocity of the bullet is 10.61 m / s, the incident rod is measured using a resistance strain gauge, and the transmission rod is measured using a semiconductor strain gauge.

[0015] Preferably, in S106, the incident rod and the transmitted rod have the same dimensions as the experimental data, and the material parameters, failure criteria and contact definitions are the same as those under static loading conditions. The established model is used for simulation analysis, and it can be obtained that the incident wave, reflected wave and transmitted wave obtained by the experiment and the numerical simulation are generally consistent with each other, indicating that the three-dimensional Voronoi model can effectively simulate the dynamic impact process of the foaming material.

[0016] Preferably, in S101, the static compression step is to use a CSS-44200 electronic universal testing machine to perform a quasi-static compression test on a 10mm×10mm×10mm specimen, with loading controlled by displacement, a speed of 0.6mm / min, and a nominal strain rate of 0.001s-1.

[0017] A foam material dynamic compression performance simulation system includes a static experiment module for statically compressing the foam material. The simulation system includes: The three-dimensional model module is used to establish a three-dimensional Voronoi finite element model of the foam material specimen, and the model size is set to be the same as the specimen size used in the test; The simulation module uses ABAQUS to perform simulation and solve, and compares the deformation of static compression simulation with that of the test when the strain reaches the same value to verify the feasibility of the three-dimensional Voronoi model; The verification module is used to compare the data obtained from the simulation with the data obtained from the actual experiment, and verify whether the data error is within the requirements, so as to verify the accuracy of the three-dimensional Voronoi model; Dynamic experiment module, using Hopkinson pressure bar equipment to conduct dynamic impact tests; Dynamic simulation module uses three-dimensional Voronoi model to perform dynamic compression simulation.

[0018] Compared with the prior art, the method and system for simulating dynamic compression performance of foaming materials provided by the present invention have the following beneficial effects: 1. The present invention first conducts a static compression test to obtain the stress-strain curve of foamed aluminum, providing test data for the verification of the three-dimensional Voronoi model. Then, the Voronoi model is used to perform quasi-static compression simulation. By comparing the stress-strain curve and compression deformation process obtained from the test, the effectiveness of the simulation model is verified. By comparing the important parameters such as yield strength, platform stress and densification strain obtained from the test, the accuracy of the simulation model is verified, laying a solid foundation for subsequent more extensive and detailed research on foamed aluminum materials. 2. The present invention uses the established model to perform simulation analysis, and can obtain that the incident wave, reflected wave and transmitted wave obtained by the experiment and the numerical simulation are generally consistent with each other, indicating that the use of the three-dimensional Voronoi model can effectively simulate the dynamic impact process of the foam material, and the simulation analysis of the foam material specimen under quasi-static compression and dynamic impact by the established three-dimensional Voronoi model is consistent with the actual test results, indicating that the use of this simulation method has high reliability and practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A flow chart of a method for simulating dynamic compression performance of a foaming material proposed by the present invention; Figure 2 A flow chart of determining the repeating unit of the foaming material according to the component ratio coefficient and building a polymer single chain structure in a method for simulating the dynamic compression performance of the foaming material proposed by the present invention; Figure 3 It is a structural schematic diagram of a foam material dynamic compression performance simulation system of the present invention; Figure 4 It is a schematic diagram of the local characteristics of a three-dimensional Voronoi model established in a method for simulating dynamic compression performance of a foam material proposed in the present invention. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0021] The implementation of the present invention is described in detail below in conjunction with specific embodiments.

[0022] The same or similar numbers in the drawings of this embodiment correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the drawings, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as limitations on the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0023] Reference Figure 1-Figure 2 As shown, a method for simulating dynamic compression performance of a foam material is applied to a simulation device and specifically comprises the following steps: S101: determining a component ratio coefficient of the foaming material to be tested, determining a repeating unit of the foaming material according to the component ratio coefficient, constructing a polymer single chain structure, and constructing an initial model of amorphous polyurethane crystal cells based on linking the polymer single chain structures; S102: using a tensile universal testing machine to statically compress the initial model of the polyurethane amorphous crystal cell, establishing a three-dimensional Voronoi finite element model of the initial model of the polyurethane amorphous crystal cell, and setting the size of the three-dimensional Voronoi finite element model to be the same as the size of the specimen used in the test; S103: Perform the initial configuration screening of the three-dimensional Voronoi finite element model to be tested, use ABAQUS to perform simulation and solution, and compare the deformation of the static compression simulation with the test when the strain reaches the same value to verify the feasibility of the three-dimensional Voronoi model; S104: obtaining a screening unit cell model based on the three-dimensional Voronoi finite element model and optimizing the screened unit cell model, processing the optimized screened unit cell model based on a molecular dynamics method to obtain a final unit cell model to be tested; S105: The final model of the unit cell to be tested is analyzed using MaterialsStudio software to obtain its structural morphology, free volume and occupancy contour. A dynamic impact test is performed using a Hopkinson pressure bar device, and a dynamic compression simulation test is performed using a three-dimensional Voronoi model to finally obtain the dynamic compression performance parameter threshold of the foaming material.

[0024] In S101, during the test, data is transmitted to the computer through the connected sensor to obtain the force-displacement curve of the compression of the foam material under this experimental condition. Since the stress-strain curve is ultimately obtained in this test, the data needs to be calculated and processed; the static compression step is to use a CSS-44200 electronic universal testing machine to perform a quasi-static compression test on a 10mm×10mm×10mm specimen, with loading controlled by displacement, a speed of 0.6mm / min, and a nominal strain rate of 0.001s-1.

[0025] Specifically, the three-dimensional Voronoi finite element model discretizes the continuum into multiple small units (elements), each of which is connected at nodes, and transmits forces and constraints through these nodes. It is mainly used for engineering analysis and predicts the response of structures or systems through numerical calculations. It is suitable for solving complex problems.

[0026] By first conducting a static compression test, the stress-strain curve of aluminum foam was obtained from the test, providing test data for the verification of the three-dimensional Voronoi model. Then, the Voronoi model was used to perform quasi-static compression simulation. By comparing the stress-strain curve and compression deformation process obtained from the test, the effectiveness of the simulation model was verified. By comparing the important parameters such as yield strength, platform stress and densification strain obtained from the test, the accuracy of the simulation model was verified, laying a solid foundation for the subsequent more extensive and detailed research on aluminum foam materials. The three-dimensional Voronoi finite element model is a model established using the finite element analysis method. It is a group of units that are connected only at nodes, transmit forces at nodes, and are constrained at nodes. This model is mainly used for engineering analysis, such as structural analysis, thermal analysis, fluid analysis, etc., to help engineers predict and evaluate product performance; 3D solid models are created through computer-aided design (CAD) software to represent the 3D geometry and physical properties of an object. They are mainly used in product design, manufacturing and simulation to help designers and engineers visualize and verify during product development. In S103, in view of the complexity of the three-dimensional Voronoi model itself, explicit dynamics is used to perform simulation solution calculation during simulation solution; In S103, by comparing the static compression stress-strain curve of the foam material obtained through the experiment with the stress-strain curve obtained through simulation, it can be seen that the two have the same trend, and both have three typical compression processes: linear elastic deformation stage, plastic platform stage and densification stage, so it can be concluded that the three-dimensional Voronoi model can effectively simulate the internal structure of the foam material.

[0027] Specifically, the nonlinear analysis function of ABAQUS has been widely recognized by high-end users in design and research. In terms of usage skills, the pre-processing and post-processing functions of ABAQUS are equally excellent. Through precise meshing, material property settings, and result visualization, users can easily manage and analyze simulation data. In addition, solving non-convergence problems, optimizing meshing, or selecting appropriate solver settings are also key steps to improve analysis accuracy. Verification The 3D Voronoi model is a geometric structure used to describe the distribution of point sets in space. It is used in materials science, geology, computer graphics and other fields. The 3D Voronoi model can be generated through specific plug-ins or software, such as the Voronoi3D plug-in generation interface in Abaqus. Users can choose to generate crystal models in the shape of a cuboid, cylinder or sphere as needed. The Voronoi class in the scipy.spatial library can also be used to generate a 3D Voronoi diagram, which is usually used to simulate foam structures, etc. In S104, in the static compression test, yield strength, platform stress and densification strain are important parameters; the yield strength is the stress corresponding to the end of the linear elastic stage and the beginning of the yield stage, the platform stress is the average stress from the beginning of entering the platform area to the end of the platform area, and the densification strain is the strain corresponding to the intersection of the straight line with the platform stress value and the tangent line of the densification stage. The important parameters such as yield strength, platform stress and densification strain obtained by the experiment are compared to verify the accuracy of the simulation model.

[0028] By first conducting a static compression test, the stress-strain curve of foamed aluminum was obtained from the experiment, providing experimental data for the verification of the three-dimensional Voronoi model. Then, the Voronoi model was used to carry out quasi-static compression simulation. The effectiveness of the simulation model was verified by comparing it with the stress-strain curve and compression deformation process obtained from the experiment. The accuracy of the simulation model was verified by comparing it with important parameters such as yield strength, platform stress and densification strain obtained from the experiment, laying a solid foundation for subsequent broader and more detailed research on foamed aluminum materials.

[0029] In S105, a 37.5mm diameter Hopkinson pressure bar device was used for dynamic impact test. The bullet length was 600mm, the incident rod and the transmission rod were both 2000mm long, the material was LC4 aluminum alloy, the cylindrical specimen had a diameter of 30mm and a height of 20mm, the impact velocity of the bullet was 10.61m / s, the incident rod was measured with a resistance strain gauge, and the transmission rod was measured with a semiconductor strain gauge; and the incident rod and the transmission rod with the same simulation data and test size, material parameters, failure criteria and contact definitions were the same as those under static loading conditions. The established model was used for simulation analysis, and it was found that the incident wave, reflected wave and transmitted wave obtained from the test and numerical simulation were generally consistent with each other, indicating that the three-dimensional Voronoi model can effectively simulate the dynamic impact process of foaming materials.

[0030] By using the established model for simulation analysis, it can be found that the incident wave, reflected wave and transmitted wave obtained from the experiment and numerical simulation are generally in good agreement, indicating that the three-dimensional Voronoi model can effectively simulate the dynamic impact process of the foam material, and the simulation analysis of the foam material specimen under quasi-static compression and dynamic impact by the established three-dimensional Voronoi model is in good agreement with the actual test results, indicating that the simulation method used is highly reliable and practical.

[0031] Reference Figure 3-Figure 4 As shown, a system for simulating dynamic compression performance of foaming materials includes a static experiment module for statically compressing foaming materials; a three-dimensional model module for establishing a three-dimensional Voronoi finite element model of a foaming material specimen, and setting the model size to be the same as the specimen size used in the test; a simulation module for using ABAQUS for simulation and solution, and comparing the deformation of the static compression simulation with the test when the strain reaches the same value, to verify the feasibility of the three-dimensional Voronoi model; a verification module for comparing the data obtained by the simulation with the data obtained by the real experiment, and verifying whether the data error is within the requirement, so as to verify the accuracy of the three-dimensional Voronoi model; a dynamic experiment module for performing dynamic impact test using a Hopkinson pressure bar device; a dynamic simulation module for performing dynamic compression simulation using a three-dimensional Voronoi model. The present invention can obtain a good overall agreement between the incident wave, reflected wave and transmitted wave obtained by the test and the numerical simulation by using the established model for simulation analysis, indicating that the three-dimensional Voronoi model can effectively simulate the dynamic impact process of the foaming material, and the established three-dimensional Voronoi The model's simulation analysis of foam material specimens under quasi-static compression and dynamic impact is in good agreement with the actual test results, indicating that the simulation method is highly reliable and practical.

[0032] refer to Figure 4The model characteristics of the three-dimensional Voronoi model are: it divides the space into multiple areas, each area corresponds to a generation point, and the distance from any point in the area to the generation point is the smallest. This model can contain grid boundaries or not, depending on the user's needs and application scenarios to ensure accuracy verification. The structural unit components of the model can simulate whether the dynamic compression performance parameters of the foaming material meet the performance required by the environment or scenario, which is convenient for experimenters to quickly obtain performance parameters.

[0033] In this embodiment, the entire operation process can be controlled by a computer to achieve automatic operation control, and in each operation link, sensors can be set to provide signal feedback to achieve sequential execution of steps. These are all common knowledge of current automatic control and will not be described in detail in this embodiment.

[0034] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for simulating dynamic compression performance of a foam material, characterized in that: Applied to analog devices, it includes the following steps: S101: determining a component ratio coefficient of the foaming material to be tested, determining a repeating unit of the foaming material according to the component ratio coefficient, constructing a polymer single chain structure, and constructing an initial model of amorphous polyurethane crystal cells based on linking the polymer single chain structures; S102: using a tensile universal testing machine to statically compress the initial model of the polyurethane amorphous crystal cell, establishing a three-dimensional Voronoi finite element model of the initial model of the polyurethane amorphous crystal cell, and setting the size of the three-dimensional Voronoi finite element model to be the same as the size of the specimen used in the test; S103: performing a preliminary configuration screening on the three-dimensional Voronoi finite element model to be tested, performing simulation and solving using ABAQUS, and comparing the deformation of the static compression simulation with the test when the strain reaches the same value to verify the feasibility of the three-dimensional Voronoi model; S104: obtaining a screening unit cell model based on the three-dimensional Voronoi finite element model and optimizing the screened unit cell model, processing the optimized screened unit cell model based on a molecular dynamics method to obtain a final unit cell model to be tested; S105: Using MaterialsStudio software to analyze the final model of the unit cell to be tested, obtain its structural morphology, free volume and occupancy contour, use Hopkinson pressure bar equipment to perform dynamic impact test, and then use three-dimensional Voronoi model to perform dynamic compression simulation test, and finally obtain the dynamic compression performance parameter threshold of the foaming material.

2. A method for simulating dynamic compression performance of a foam material according to claim 1, characterized in that: In S101, the component ratio coefficient of the foaming material to be tested is determined, and the repeating unit of the foaming material is determined according to the component ratio coefficient, and a polymer single chain structure is constructed, including: Adding two-dimensional carbon / nitrogen / carbonitride material and high-temperature foaming agent to polyether alcohol successively to fully react, cooling and adding glycidyl ether curing agent to obtain uniform repeating units of polyether alcohol mixture foaming material; In a nitrogen-flushing environment, the repeating units of the thermoplastic polyether ester elastomer and the polyether alcohol mixture foaming material which have been dried are added into a reaction kettle and mixed evenly, and the copolymerized thermoplastic polyether ester elastomer polymer single chain structure is obtained by pressurized extrusion in a molten state.

3. A method for simulating dynamic compression performance of a foam material according to claim 2, characterized in that: In S102, during the test, data is transmitted to a computer through a connected sensor to obtain a force-displacement curve of the compression of the foam material under the experimental conditions. Since the test ultimately aims to obtain a stress-strain curve, the data needs to be calculated and processed.

4. A method for simulating dynamic compression performance of a foam material as claimed in claim 3, characterized in that: In S103, in view of the complexity of the three-dimensional Voronoi model itself, explicit dynamics is used to perform simulation solution calculation during simulation solution.

5. A method for simulating dynamic compression performance of a foam material according to claim 4, characterized in that: Explicit dynamics is used for simulation and solution. The calculation method is as follows: comparing the static compression stress-strain curve of the foam material obtained through the experiment with the stress-strain curve obtained through simulation, it can be seen that the two have the same trend, and both have three typical compression processes: linear elastic deformation stage, plastic platform stage and densification stage, so it can be concluded that the three-dimensional Voronoi model can effectively simulate the internal structure of the foam material.

6. A method for simulating dynamic compression performance of a foam material according to claim 5, characterized in that: In S104, in the static compression test, yield strength, platform stress and densification strain are important parameters, where yield strength is the stress at the end of the linear elastic stage and the beginning of the yield stage, platform stress is the average stress from the beginning of the platform zone to the end of the platform zone, and densification strain is the strain corresponding to the intersection of the straight line with the platform stress value and the tangent line of the densification stage. The important parameters such as yield strength, platform stress and densification strain obtained by the experiment are compared to verify the accuracy of the simulation model.

7. A method for simulating dynamic compression performance of a foam material according to claim 6, characterized in that: In S105, a dynamic impact test is performed using a Hopkinson pressure bar apparatus, including: A dynamic impact test was carried out using a Hopkinson pressure bar device with a diameter of 37.5 mm. The bullet length was 600 mm, the incident rod and the transmission rod were both 2000 mm long, the material was LC4 aluminum alloy, the cylindrical specimen had a diameter of 30 mm and a height of 20 mm, the impact velocity of the bullet was 10.61 m / s, a resistance strain gauge was used for the incident rod, and a semiconductor strain gauge was used for the transmission rod for measurement.

8. A method for simulating dynamic compression performance of a foam material according to claim 7, characterized in that: Then use the 3D Voronoi model to perform dynamic compression simulation tests, including: The incident and transmitted rods of the simulation data have the same dimensions as those of the test, and the material parameters, failure criteria, and contact definitions are the same as those under static loading conditions; The simulation analysis using the established model shows that the incident wave, reflected wave and transmitted wave obtained from the experiment and numerical simulation are generally in good agreement, indicating that the three-dimensional Voronoi model can effectively simulate the dynamic impact process of foaming materials.

9. A method for simulating dynamic compression performance of a foam material according to claim 8, characterized in that: The static compression step is to use a CSS-44200 electronic universal testing machine to perform a quasi-static compression test on a 10mm×10mm×10mm specimen, with the loading controlled by displacement, a speed of 0.6mm / min, and a nominal strain rate of 0.001s-1.

10. A foam material dynamic compression performance simulation system, characterized in that: The method for simulating dynamic compression performance of a foam material according to any one of claims 1 to 9, wherein the performance simulation system comprises: Static test module, used for static compression of foaming materials; The three-dimensional model module is used to establish a three-dimensional Voronoi finite element model of the foam material specimen, and the model size is set to be the same as the specimen size used in the test; The simulation module uses ABAQUS to perform simulation and solve, and compares the deformation of static compression simulation with that of the test when the strain reaches the same value to verify the feasibility of the three-dimensional Voronoi model; The verification module is used to compare the data obtained from the simulation with the data obtained from the actual experiment, and verify whether the data error is within the requirements, so as to verify the accuracy of the three-dimensional Voronoi model; Dynamic experiment module, using Hopkinson pressure bar equipment to carry out dynamic impact test; Dynamic simulation module uses three-dimensional Voronoi model to perform dynamic compression simulation.

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