Simulation method of abrasive jet machining of particle reinforced composites based on discrete element method

Abstract

The present invention discloses a method for simulating abrasive jet machining of particle-reinforced composite materials based on a discrete element method, comprising: obtaining machining process simulation parameters according to an actual machining system; establishing a geometric model of an abrasive jet and a composite material at a millimeter scale, dividing a structured grid based on the finite element method to perform macroscopic mechanical simulation calculations of the abrasive jet and the plate, and obtaining the stress and dynamic pressure distribution on the surface of the composite material; establishing a geometric model of the composite material particle phase and matrix phase at a micrometer scale, dividing an unstructured grid based on the finite element method, and setting the material parameters of the particle phase and matrix phase, applying the surface stress and dynamic pressure distribution results of the material in the millimeter-scale simulation calculation as pressure boundary conditions to the upper surface of the matrix phase geometric model in the micrometer-scale model, and performing continuous simulation calculations. The present invention provides guidance for abrasive jet machining of particle-reinforced composite materials, reduces trial and error costs, and improves the efficiency of abrasive jet machining of particle-reinforced composite materials.

Description

Technical Field

[0001] The present application relates to the technical field of jet machining, and in particular to a cross-scale simulation method for abrasive jet machining of particle-reinforced composite materials based on a discrete element method. Background Art

[0002] As a new type of material, particle reinforced composite materials have a series of excellent physical and mechanical properties such as low density, high specific strength, high specific stiffness, high temperature resistance, fatigue resistance, and corrosion resistance. Because they can be manufactured using a series of basic processing technologies such as powder metallurgy, forging, and forging, they are widely used in many fields such as aerospace, automobiles, optical precision devices, and the electronics industry.

[0003] Currently, the processing of particle-reinforced composites (PRCs) is still in the trial-and-error research phase, requiring high labor and material costs, which limits the development of PRC processing technology. Furthermore, reliable experimental techniques and methods are lacking to investigate the stress, deformation, and damage formation processes during PRC processing. Summary of the Invention

[0004] This application develops a cross-scale simulation method for abrasive jet processing of particle-reinforced composite materials, establishes a process parameter control model for different processing requirements, and can effectively reveal the dynamic pressure and residual stress distribution on the surface of particle-reinforced composite materials, the different damage changes and processing contour changes of the internal particle phase and matrix phase under the action of abrasive particles, and establishes a process parameter control model for different processing requirements, providing a reference for abrasive jet processing of particle-reinforced composite materials and improving processing efficiency.

[0005] In a first aspect, a method for simulating abrasive jet machining of particle-reinforced composite materials based on a discrete element method is provided, characterized by comprising:

[0006] According to the actual processing system, obtain the processing simulation parameters, including geometric dimensions, material physical parameters and related dynamic parameters;

[0007] A geometric model of the abrasive jet and composite material was established at the millimeter scale. The structured grid was divided based on the finite element method. Water particle units and abrasive particle units were established based on the SPH method and the DEM method, respectively. The material parameters of the abrasive, water, and plate were set. The interaction between the abrasive particles was set based on the discrete element method. The interaction between the abrasive particles and the plate was set based on the Archard wear contact model. The water and plate contact model was set based on the Lagrangian method. Macroscopic mechanical simulation calculations of the abrasive jet and the plate were performed to obtain the stress and dynamic pressure distribution on the composite surface.

[0008] The geometric model of the particle phase and matrix phase of the composite material is re-established at the micron scale. The unstructured grid is divided based on the finite element method, and the material parameters of the particle phase and matrix phase are set. The damage evolution mode of the particle phase and matrix phase is set based on the Johnson-Cook damage model. The interaction between the particle phase and the matrix phase is set based on the consolidation contact model. The surface stress and dynamic pressure distribution results of the material in the millimeter-level simulation calculation are used as pressure boundary conditions to act on the upper surface of the matrix phase geometric model in the micron-level model. Continuous simulation calculations are performed to obtain the damage changes of the particle phase and the processing contour, damage evolution process and residual stress distribution of the matrix phase.

[0009] In combination with the first aspect, in certain implementations of the first aspect, the geometric dimensions of the processing system include target distance, nozzle diameter, and abrasive particle diameter; the physical parameters of the processing system include water density, cut-off pressure, bulk modulus, density of abrasive particles, Young's modulus, Poisson's ratio, density of composite materials, Young's modulus, and Poisson's ratio; the dynamic parameters of the processing system include the initial velocity of the jet, dynamic viscosity coefficient, and particle state equation.

[0010] In combination with the first aspect, in certain implementations of the first aspect, the geometric parameters of the composite material include workpiece size, particle size, and particle distribution; the physical parameters of the composite material include material density, Young's modulus, and Poisson's ratio.

[0011] In conjunction with the first aspect, in certain implementations of the first aspect, the simulation of the abrasive jet and the composite material includes:

[0012] Using the Shape Mesher module of LS-DYNA, a millimeter-scale geometric model of the abrasive jet and the composite material was established according to the geometric dimensions in S1, and the composite material was meshed based on the finite element method.

[0013] Use the SPH Generation block of LS-DYNA to generate SPH particles based on the 3D geometric model of the abrasive jet. Use the Disc Sphere Generation block of LS-DYNA to generate DEM particles at the center of the geometric model. Use the discrete element method to set the contact force and damping interaction conditions between the particles. Set the interaction between the abrasive particles and the plate based on the Archard wear contact model. Set the interaction between water and the plate based on the Lagrangian method. Establish a mesh model of the abrasive jet.

[0014] The Keyword Manager module of LS-DYNA was used to set the initial velocity, contact type, boundary conditions, hourglass control, and unit attribute keywords of the jet model according to the physical parameters and dynamic parameters in S1. The millimeter-level processing model was simulated and calculated to obtain the stress and dynamic pressure distribution on the composite material surface.

[0015] In conjunction with the first aspect, in certain implementations of the first aspect, a method for simulating a composite material particle phase and a matrix phase includes:

[0016] Using the Shape Mesher module of LS-DYNA, a micron-scale geometric model of the SiC particles and the Al matrix in the composite material was established. The mesh was divided based on the finite element method, and a consolidated contact was set between the SiC particle mesh and the Al matrix mesh to obtain a micron-scale composite mesh model.

[0017] The Keyword Manager module of LS-DYNA was used to set the contact type, boundary conditions, hourglass control, and element property keywords according to the physical and dynamic parameters in S1. The initial conditions of the micron-level model were set based on the stress distribution and dynamic pressure results obtained from the millimeter-level machining model simulation. The micron-level machining model was simulated and calculated to obtain the different damage changes and machining profile changes of the particle phase and matrix phase inside the composite material under the action of abrasive particles.

[0018] In conjunction with the first aspect, in certain implementations of the first aspect, the millimeter-level abrasive jet and the composite material mesh model have a jet action core area, the millimeter-level target node on the jet action core area corresponds to a surface stress distribution result and / or a material surface dynamic pressure result, the position of the micron-level target node of the micron-level machining model corresponds to the position of the millimeter-level target node, and setting the initial conditions of the micron-level model based on the stress distribution and dynamic pressure results obtained by simulation of the millimeter-level machining model includes:

[0019] The surface stress distribution result of the millimeter-level target node and / or the material surface dynamic pressure result are set as constraint conditions on the micron-level target node.

[0020] In conjunction with the first aspect, in certain implementations of the first aspect, the millimeter-level abrasive jet and composite material mesh model has a jet action core area, and the millimeter-level target nodes on the jet action core area correspond to surface stress distribution results and / or material surface dynamic pressure results. Setting the initial conditions of the micron-level model based on the stress distribution and dynamic pressure results obtained by simulating the millimeter-level machining model includes:

[0021] Extracting the coordinates of the millimeter-level target node;

[0022] According to the coordinates of the millimeter-level target node, the surface stress distribution result of the millimeter-level target node and / or the material surface dynamic pressure result are added as constraint conditions at the corresponding position of the micron-level geometric model.

[0023] In conjunction with the first aspect, in certain implementations of the first aspect, the millimeter-level abrasive jet and composite material mesh model has a jet action core area, and the millimeter-level target nodes on the jet action core area correspond to surface stress distribution results and / or material surface dynamic pressure results. Setting the initial conditions of the micron-level model based on the stress distribution and dynamic pressure results obtained by simulating the millimeter-level machining model includes:

[0024] Smoothing the surface stress distribution results and / or the material surface dynamic pressure results corresponding to the core area of ​​the jet action, and determining a variation band of the surface stress distribution results and / or the material surface dynamic pressure results in the core area of ​​the jet action;

[0025] According to the geometric position of the change zone on the core area of ​​the jet action, the surface stress distribution result and / or the material surface dynamic pressure result are set as constraint conditions on the micron-scale geometric model.

[0026] In conjunction with the first aspect, in some implementations of the first aspect, the method further includes:

[0027] The abrasive jet composite material processing experiment was carried out with the same process parameters, and the processing profile obtained from the experiment was compared with the simulation results to verify the reliability of the simulation results and further optimize the simulation process.

[0028] In conjunction with the first aspect, in some implementations of the first aspect, the method further includes:

[0029] The simulation experimental calculation results are analyzed to obtain the relationship between the surface damage defects, cracks, cavities, residual stresses and simulation process parameters that appear during the processing process. The process parameters are summarized and sorted to form a particle reinforced composite abrasive jet processing process database.

[0030] Compared with the existing technology, the solution provided by this application includes at least the following beneficial technical effects:

[0031] The present invention starts from the geometric parameters, physical parameters, and dynamic parameters of the abrasive jet processing of particle-reinforced composite materials, sets the interaction between abrasive particles based on the discrete element method, simulates the state of the abrasive in the jet, and calculates the stress and dynamic pressure on the surface of the composite material during the processing through a multi-scale coupled simulation method. It explores the different damage changes and processing profile changes of the particle phase and matrix phase inside the composite material under the action of abrasive particles, analyzes the surface damage defects, cracks, cavities, residual stresses, etc. that appear during the processing quality and processing of the particle-reinforced composite material, summarizes the process parameters, and establishes a process parameter control model. The present invention can effectively guide the abrasive jet processing of particle-reinforced composite materials, reduce the cost of trial and error, and improve the efficiency of the abrasive jet processing of particle-reinforced composite materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a flow chart of a cross-scale simulation method for abrasive jet machining of particle-reinforced composite materials according to one embodiment of the present invention.

[0033] Figure 2 It is a data interaction and system framework diagram of a cross-scale simulation method for abrasive jet machining of particle-reinforced composite materials according to an embodiment of the present invention.

[0034] Figure 3 It is a schematic diagram of a cross-scale simulation model of abrasive jet machining of particle-reinforced composite materials according to an embodiment of the present invention. DETAILED DESCRIPTION

[0035] The present application is described in further detail below with reference to the accompanying drawings and specific embodiments.

[0036] In a typical abrasive jet machining process for particle-reinforced composites, a high-pressure abrasive jet is ejected from a nozzle, physically impacting the surface of the particle-reinforced composite. The high-speed impact of the abrasive gradually removes the composite's base particles, achieving the desired cutting process. This entire process involves complex physical processes such as fluid motion, micro-stresses, and large deformations, and is influenced by numerous process parameters, necessitating a set of efficient and low-cost testing methods to guide these parameters.

[0037] Particle-reinforced composites are composite materials composed of a particle phase and a matrix phase. The particle size of the material is generally small. For example, in SiCp / Al materials, the particle size of SiC particles is mostly micron-sized, and may even reach several microns. However, during abrasive jet machining, the size of the workpiece is generally millimeter-sized, which poses certain problems for the accurate simulation of abrasive jet machining of particle-reinforced composites. Therefore, one of the innovations of the present invention is to first establish a millimeter-scale machining system grid model, calculate and obtain simulation results, and simultaneously establish a more refined micron-scale machining system grid model. The results of the millimeter-scale simulation calculations are used as initial conditions for continuous simulation calculations. By coupling the multi-scale simulation calculation results, accurate simulation of particle-reinforced composite jet machining is achieved.

[0038] Figure 1 、 Figure 2 and Figure 3 The cross-scale simulation method of the abrasive jet processing process of particle-reinforced composite materials shown is used to simulate the stress and dynamic pressure distribution on the surface of the composite material, the different damage changes of the particle phase and the matrix phase inside the composite material under the action of abrasive particles, and the processing profile changes in the multi-scale coupling process of the abrasive jet processing process of particle-reinforced composite materials.

[0039] S1, according to the actual processing system, obtain the processing process simulation parameters, including geometric dimensions, material physical parameters and related dynamic parameters.

[0040] S2: Establish a millimeter-scale geometric model of the abrasive jet and composite material. Create a structured mesh using the finite element method. Create water particle units and abrasive particle units using the SPH and DEM methods, respectively. Set the material parameters for the abrasive, water, and plate. Define the interaction between abrasive particles using the discrete element method, the interaction between abrasive particles and plate using the Archard wear contact model, and the water-plate contact model using the Lagrangian method. Perform macroscopic mechanical simulations of the abrasive jet and plate to obtain the stress and dynamic pressure distribution on the composite surface.

[0041] S3 re-establishes the geometric model of the composite material's particle and matrix phases at the micron scale. Finite element method-based meshing is used to create an unstructured grid, and the material parameters for the particle and matrix phases are set. The damage evolution of the particle and matrix phases is then determined based on the Johnson-Cook damage model. The interaction between the particle and matrix phases is set based on a consolidation contact model. The surface stress and dynamic pressure distributions from millimeter-scale simulations are applied as pressure boundary conditions to the upper surface of the matrix phase geometry in the micron-scale model. Continuous simulations are performed to determine the damage changes in the particle phase, the machining contours of the matrix phase, the damage evolution process, and the residual stress distribution.

[0042] Step S1 specifically includes: establishing an abrasive jet impact and composite material processing process data model based on the geometric dimensions, physical parameters, dynamic parameters, and process methods in the abrasive jet processing process through dynamic data modeling, which includes a process material database and an equipment technical parameter database.

[0043] In step S1, the geometric dimensions of the processing system include target distance, nozzle diameter, and abrasive particle diameter. Physical parameters of the processing system include water density, shear pressure, bulk modulus, abrasive particle density, Young's modulus, and Poisson's ratio. Dynamic parameters of the processing system include the initial velocity of the jet, dynamic viscosity coefficient, and particle equation of state.

[0044] In step S1, the geometric parameters of the composite material 3D model include workpiece dimensions, particle size, and particle distribution. The physical parameters of the composite material 3D model include material properties such as density, Young's modulus, Poisson's ratio, and the parameters of the constitutive model selected for the material.

[0045] In step S2, first, a millimeter-scale geometric model of the abrasive jet and the composite material is established according to the relevant simulation parameters in S1, and the solid structured grid is divided based on the finite element method. Then, the SPH particle generation module in LS-DYNA is used to generate SPH particles according to the geometric model. The DEM particle generation module in LS-DYNA is used to generate DEM particles in the center of the jet geometric model. The interaction between the particles is defined based on the discrete element method, and the relevant simulation parameters are set. The millimeter-scale simulation calculation is performed to obtain the stress and dynamic pressure distribution on the surface of the composite material.

[0046] In one embodiment provided in this application, the height of the nozzle outlet from the plate is 2 mm, the nozzle diameter is 1 mm, the length and width of the composite material are both 30 mm, and the thickness is 20 mm. The water jet adopts the MAT_NULL material model and combines the Murnaghan equation of state (EOS) to describe the fluid characteristics of water. Under high pressure, the density of water is 998.2 kg / m 3 , the dynamic viscosity coefficient is 1.02x10 - 3 Pa s, the cut-off pressure is -1.0x10 20 Pa, and the bulk modulus is 2.22x10 9 Pa. The state equation parameters for high pressure water are as follows: GAMMA is 7, K0 is 8.0213x10 9 , V0 is 0. The density of the abrasive is 4120kg / m 3 , Young's modulus is 248GPa, and Poisson's ratio is 0.3.

[0047] The specific implementation of step S2 is as follows.

[0048] Using the Shape Mesher module of LS-DYNA, a millimeter-scale geometric model of the abrasive jet and the composite material was established according to the geometric dimensions in S1, and the composite material was meshed based on the finite element method.

[0049] The SPH Generation block of LS-DYNA was used to generate SPH particles according to the three-dimensional geometric model of the abrasive jet. The Disc Sphere Generation block of LS-DYNA was used to generate DEM particles at the center of the geometric model. The contact force, damping and other interaction conditions between the particles were set according to the discrete element method. The interaction between the abrasive particles and the plate was set based on the Archard wear contact model. The interaction between water and the plate was set based on the Lagrangian method. Finally, a mesh model of the abrasive jet was established.

[0050] The Keyword Manager module of LS-DYNA was used to set the initial velocity, contact type, boundary conditions, hourglass control, element properties and other keywords of the jet model according to the physical parameters and dynamic parameters in S1. The millimeter-level processing model was simulated and calculated to obtain the stress and dynamic pressure distribution on the composite material surface.

[0051] In step S3, the geometric model of the composite material is refined and remodeled, and the SiC particle phase and Al matrix phase at the micron scale are established to construct a micron-scale composite material geometric model. Then, the unstructured grid is divided based on the finite element method, and the SiC particle phase and the matrix phase grid connected to it are locally encrypted. The particle phase and matrix phase material parameters and damage evolution model are set, and the stress and dynamic pressure distribution on the material surface calculated in S2 are used as pressure boundary conditions to act on the upper surface of the matrix phase geometric model in the micron-scale model, and continuous simulation calculations are performed to calculate the damage changes of the particle phase and the processing contour of the matrix phase, the damage evolution process and the residual stress distribution.

[0052] In one embodiment provided in this application, the Johnson-Cook constitutive model is combined with the Gruneisen equation of state (EOS) to describe the properties of the particle reinforcement material. The Al density of the matrix material is 2.82x10 3 kg / m 3 , Young's modulus is 70.6GPa, Poisson's ratio is 0.35, melting temperature is 900K, thermal conductivity is 180mW / mm*K, the size of the granular SiC particles is 8μm, the material properties are, density is 3.2x10 3 kg / m 3 , Young's modulus is 40.8GPa, Poisson's ratio is 0.35, compressive strength is 3900MPa, and thermal conductivity is 120mW / mm*K.

[0053] The specific implementation of step S3 is as follows.

[0054] The Shape Mesher module of LS-DYNA was used to establish a micron-scale geometric model of SiC particles and Al matrix in the composite material. The mesh was divided based on the finite element method, and the consolidation contact between the SiC particle mesh and the Al matrix mesh was set to obtain a micron-scale composite material mesh model.

[0055] The Keyword Manager module of LS-DYNA was used to set keywords such as contact type, boundary conditions, hourglass control, and element properties based on the physical and dynamic parameters in S1. The initial conditions of the micron-level model were set based on the stress distribution and dynamic pressure results obtained from the millimeter-level machining model simulation. The micron-level machining model was simulated and calculated to obtain the different damage changes and machining profile changes of the particle phase and matrix phase inside the composite material under the action of abrasive particles.

[0056] The specific implementation method of the millimeter-level grid loading on the micron-level model is to extract the surface stress distribution results of the composite material and / or the surface dynamic pressure results of the material obtained by the millimeter-level grid model, and then introduce the curve of the surface stress distribution results and / or the surface dynamic pressure results of the material into the micron-level composite material model as the initial loading condition to simulate the impact of the jet, thereby increasing the simulation efficiency. The grid of the millimeter-level abrasive jet and composite material grid model is coarser than the grid of the micron-level composite material particle phase and matrix phase model. The embodiments of the present application provide multiple ways to achieve this. Among them, the surface stress distribution results can represent the impact of the model on the inside of the material after being cut by the abrasive jet. The surface dynamic pressure results of the material can represent the external force of the abrasive jet on the composite material. In water jet processing, the jet diameter is generally small, and the SiC / Al workpiece in the core area of ​​the jet action is selected to establish a millimeter-level jet simulation model, which is also the area where material removal mainly occurs.

[0057] In one embodiment, there is a jet action core area between the millimeter-level abrasive jet and the composite material grid model, that is, the area where the abrasive jet hits the composite material, and the millimeter-level target node on the jet action core area corresponds to the surface stress distribution result and / or the material surface dynamic pressure result. The position of the micron-level target node of the micron-level processing model corresponds to the position of the millimeter-level target node, for example, the micron-level target node is the node closest to the millimeter-level target node on the micron-level processing model. The surface stress distribution result and / or the material surface dynamic pressure result of the millimeter-level target node are set as constraint conditions on the micron-level target node.

[0058] In another embodiment, the coordinates of a millimeter-scale target node in the core area of ​​the jet action are extracted. Based on these coordinates, the surface stress distribution results and / or the material surface dynamic pressure results of the millimeter-scale target node are added as constraints at the corresponding position of the micron-scale geometric model. The micron-scale geometric model is the geometric model of the micron-scale machining model.

[0059] In yet another embodiment, the surface stress distribution results and / or the material surface dynamic pressure results corresponding to the core area of ​​the jet action are smoothed to determine a variation band for the surface stress distribution results and / or the material surface dynamic pressure results in the core area of ​​the jet action. Based on the geometric position of the variation band within the core area of ​​the jet action, the surface stress distribution results and / or the material surface dynamic pressure results are then applied as constraints to the micron-scale geometric model.

[0060] In steps S2 and S3, geometric modeling software such as SolidWorks can be used to create a three-dimensional geometric model of the abrasive jet composite material processing process, and the model can be imported into simulation software for finite element meshing and simulation calculation.

[0061] After executing step S3, the same process parameters can be used to perform abrasive jet material processing experiments. The processing profile obtained from the experiment is compared with the simulation results of the millimeter-level model to verify the reliability of the simulation results and further optimize the simulation process. During the jet impact simulation process, a material removal process will occur, and the results such as cutting depth and width will be displayed after the simulation. These results will be extracted and compared with the actual processing profile of the experiment. In the experimental processing process, the micromorphology and defects of the cutting groove or hole wall are compared with the removal of SiC particles observed in the simulation results of the micron-level model and the crack phenomenon generated in the simulation.

[0062] After executing step S3, step S4 can be executed to analyze the simulation experiment calculation results, explore the relationship between the surface damage defects, cracks, cavities, residual stresses and simulation process parameters that appear during the processing process, and summarize the process parameters to form a particle-reinforced composite abrasive jet processing process database, provide predictable results for actual processing, make parameter adjustment guidance, and provide data support for the subsequent optimization of process parameters.

[0063] Although the present invention is disclosed above in terms of preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be based on the scope defined by the claims of the present invention.

Claims

1. A simulation method for abrasive jet machining of particle-reinforced composite materials based on discrete element method, characterized in that: include: According to the actual processing system, obtain the processing simulation parameters, including geometric dimensions, material physical parameters and related dynamic parameters; A geometric model of the abrasive jet and composite material was established at the millimeter scale. The structured grid was divided based on the finite element method. Water particle units and abrasive particle units were established based on the SPH method and the DEM method, respectively. The material parameters of the abrasive, water, and plate were set. The interaction between the abrasive particles was set based on the discrete element method. The interaction between the abrasive particles and the plate was set based on the Archard wear contact model. The water and plate contact model was set based on the Lagrangian method. Macroscopic mechanical simulation calculations of the abrasive jet and the plate were performed to obtain the stress and dynamic pressure distribution on the composite surface. The geometric model of the composite material particle phase and matrix phase was re-established at the micron scale. The unstructured grid was divided based on the finite element method, and the material parameters of the particle phase and matrix phase were set. The damage evolution mode of the particle phase and matrix phase was set based on the Johnson-Cook damage model. The interaction between the particle phase and matrix phase was set based on the consolidation contact model. The surface stress and dynamic pressure distribution results of the material in the millimeter-level simulation calculation were used as pressure boundary conditions to act on the upper surface of the matrix phase geometric model in the micron-level model. Continuous simulation calculations were performed to obtain the damage changes of the particle phase and the processing contour of the matrix phase, the damage evolution process and the residual stress distribution; Simulation of abrasive jets and composites includes: Using the Shape Mesher module of LS-DYNA, a millimeter-scale geometric model of the abrasive jet and composite material was established based on the geometric dimensions, and the composite material was meshed using the finite element method. Use the SPH Generation block of LS-DYNA to generate SPH particles based on the 3D geometric model of the abrasive jet. Use the Disc Sphere Generation block of LS-DYNA to generate DEM particles at the center of the geometric model. Use the discrete element method to set the contact force and damping interaction conditions between the particles. Set the interaction between the abrasive particles and the plate based on the Archard wear contact model. Set the interaction between water and the plate based on the Lagrangian method. Establish a mesh model of the abrasive jet. Use the Keyword Manager module of LS-DYNA to set the initial velocity, contact type, boundary conditions, hourglass control, and element attribute keywords of the jet model based on physical and dynamic parameters. Simulate the millimeter-level processing model to obtain the stress and dynamic pressure distribution on the composite material surface. Simulation methods for composite material particle phase and matrix phase include: Using the Shape Mesher module of LS-DYNA, a micron-scale geometric model of the SiC particles and the Al matrix in the composite material was established. The mesh was divided based on the finite element method, and a consolidated contact was set between the SiC particle mesh and the Al matrix mesh to obtain a micron-scale composite mesh model. The Keyword Manager section of LS-DYNA is used to set the contact type, boundary conditions, hourglass control, and element property keywords according to the physical parameters and dynamic parameters. The initial conditions of the micron-level model are set based on the stress distribution and dynamic pressure results obtained from the millimeter-level processing model simulation. The micron-level processing model is simulated and calculated to obtain the different damage changes and processing profile changes of the particle phase and matrix phase inside the composite material under the action of abrasive particles.

2. The simulation method according to claim 1, wherein: The geometric dimensions of the processing system include target distance, nozzle diameter, and abrasive particle diameter; the physical parameters of the processing system include water density, cutting pressure, bulk modulus, density of abrasive particles, Young's modulus, Poisson's ratio, and density of composite materials; the dynamic parameters of the processing system include the initial velocity of the jet, dynamic viscosity coefficient, and particle state equation.

3. The simulation method according to claim 1, wherein: The geometric parameters of composite materials include workpiece size, particle size, and particle distribution; the physical parameters of composite materials include material density, Young's modulus, and Poisson's ratio.

4. The simulation method according to claim 1, wherein: The millimeter-level abrasive jet and composite material mesh model has a jet action core area, and the millimeter-level target nodes on the jet action core area correspond to surface stress distribution results and / or material surface dynamic pressure results. The position of the micron-level target node of the micron-level processing model corresponds to the position of the millimeter-level target node. The initial conditions of the micron-level model are set based on the stress distribution and dynamic pressure results obtained by simulating the millimeter-level processing model, including: The surface stress distribution result of the millimeter-level target node and / or the material surface dynamic pressure result are set as constraint conditions on the micron-level target node.

5. The simulation method according to claim 1, wherein: The millimeter-level abrasive jet and composite material mesh model has a jet action core area. The millimeter-level target nodes on the jet action core area correspond to surface stress distribution results and / or material surface dynamic pressure results. The stress distribution and dynamic pressure results obtained based on the millimeter-level machining model simulation are used to set the initial conditions of the micron-level model, including: Extracting the coordinates of the millimeter-level target node; According to the coordinates of the millimeter-level target node, the surface stress distribution result of the millimeter-level target node and / or the material surface dynamic pressure result are added as constraint conditions at the corresponding position of the micron-level geometric model.

6. The simulation method according to claim 1, wherein: The millimeter-level abrasive jet and composite material mesh model has a jet action core area. The millimeter-level target nodes on the jet action core area correspond to surface stress distribution results and / or material surface dynamic pressure results. The stress distribution and dynamic pressure results obtained based on the millimeter-level machining model simulation are used to set the initial conditions of the micron-level model, including: Smoothing the surface stress distribution results and / or the material surface dynamic pressure results corresponding to the core area of ​​the jet action, and determining a variation band of the surface stress distribution results and / or the material surface dynamic pressure results in the core area of ​​the jet action; According to the geometric position of the change zone on the core area of ​​the jet action, the surface stress distribution result and / or the material surface dynamic pressure result are set as constraint conditions on the micron-scale geometric model.

7. The simulation method according to claim 1, wherein: The method further comprises: The abrasive jet composite material processing experiment was carried out with the same process parameters, and the processing profile obtained from the experiment was compared with the simulation results to verify the reliability of the simulation results and further optimize the simulation process.

8. The simulation method according to claim 1, wherein: The method further comprises: The simulation experimental calculation results are analyzed to obtain the relationship between the surface damage defects, cracks, cavities, residual stresses and simulation process parameters that appear during the processing process. The process parameters are summarized and sorted to form a particle reinforced composite abrasive jet processing process database.

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