A dual-scale coupled finite element simulation method for metal matrix composites

Abstract

The present invention discloses a dual-scale coupled finite element simulation method for metal matrix composite materials, and belongs to the technical field of metal matrix composite material deformation process simulation. The method couples the metal matrix composite material component scale simulation and the reinforcement scale simulation through a database, uses the component scale simulation result to provide boundary conditions and other data for the reinforcement scale simulation, uses the reinforcement scale simulation to provide constitutive relations and stiffness matrix and other data for the component scale simulation, and uses the database to connect the two scales of reinforcement and component to improve the reusability of the reinforcement scale simulation and improve the calculation efficiency. The method realizes the dual-scale coupled simulation of metal matrix composite materials in the plastic processing process. The dual-scale coupled simulation method can be used to analyze the flow deformation behavior of two scales in the deformation process, which can assist the plastic processing process design of metal matrix composite materials and reduce the cost and cycle of process and mold design.

Description

Technical Field

[0001] The invention relates to the technical field of metal matrix composite material deformation process simulation, and in particular to a dual-scale coupled finite element simulation method for metal matrix composite materials. Background Art

[0002] Metal matrix composites have advantages that single metal materials do not have, such as high specific modulus, high specific strength and good dimensional stability. They are key strategic materials in many key fields such as aerospace, nuclear power and weapons. SiC / Al composites have been successfully used in Mars wheels and lunar soil drilling and mining mechanisms; B4C / Al has also been successfully applied as a key material for spent fuel storage containers in the nuclear power field. However, due to the huge difference in the properties of the reinforcement phase and the metal matrix, the deformation of the two scales of the component and the reinforcement during the plastic processing of metal matrix composites is extremely complex. During the plastic processing of the component, the deformation flow behavior of the reinforcement and matrix in different regions of the component is different, resulting in different mechanical properties in different regions of the component scale, and it is very difficult to accurately predict the overall deformation behavior of the component. Therefore, it is difficult to control the deformation processing process through a single-scale numerical simulation method like a single metal material. Due to the lack of effective numerical simulation methods, the plastic processing process of metal matrix composites is difficult to control at present, and the trial and error cost of process control is high and the cycle is long, which limits the application scope of metal matrix composites. Therefore, it is necessary to develop a dual-scale coupled numerical simulation method for the deformation behavior of the component scale and the reinforcement scale involved in the deformation processing of metal matrix composites, so as to realize the dual-scale numerical simulation of the plastic processing of metal matrix composites, thereby assisting in the design of its plastic processing technology.

[0003] At present, the dual-scale coupling simulation method for composite materials generally adopts a one-way coupling mode, that is, only the component scale simulation results are considered to provide boundary conditions for the reinforcement scale simulation results, simulating the deformation flow of reinforcements and matrix in different regions of the component, thereby analyzing the mechanical properties of different regions of the component, without considering the influence of the change of reinforcement scale on the deformation behavior of the component scale. The simulation from reinforcement scale to component scale is mainly aimed at elastic deformation or small deformation process. For example, the literature (Engineering with Computers 35 (2019) 567–577) simulates the small deformation of the reinforcement scale of carbon fiber reinforced composite materials, and simulates and calculates by applying 6 different boundary conditions, providing parameters such as equivalent modulus and Poisson's ratio for the simulation of component scale. For the dual-scale coupling simulation of large plastic deformation processes, it is necessary to consider the bidirectional coupling of the reinforcement scale and the component scale during the deformation process. During the calculation process, complex boundary conditions need to be designed for the reinforcement scale, and the reinforcement scale simulation calculation is performed for each incremental step of each unit of the component scale. As a result, the calculation amount of the reinforcement scale simulation is proportional to the number of component scale grids. The reinforcement scale simulation calculation is not reusable, the calculation time is too high, and it is difficult to apply and promote. Summary of the invention

[0004] The purpose of the present invention is to provide a dual-scale coupled finite element simulation method for metal matrix composite materials, which couples the metal matrix composite material component scale simulation and reinforcement scale simulation through a database, uses the component scale simulation results to provide boundary conditions and other data for the reinforcement scale simulation, uses the reinforcement scale simulation to provide constitutive relations and stiffness matrix and other data for the component scale simulation, and uses the database to connect the two scales of reinforcement and component to improve the reusability of reinforcement scale simulation and improve calculation efficiency. This method realizes dual-scale coupled simulation of metal matrix composite materials during plastic processing. The dual-scale coupled simulation method can be used to analyze the flow deformation of two scales during the deformation process, which can assist in the design of plastic processing technology of metal matrix composite materials and reduce the cycle and cost of process and mold design.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] A dual-scale coupled finite element simulation method for metal matrix composites, which includes the following three parts:

[0007] (1) Database part

[0008] The database mainly stores the conditions and results of the reinforcement scale simulation calculation. The equivalent stiffness matrix, constitutive relationship and other calculation results after the reinforcement scale deformation can be queried through information such as material component characteristics and boundary conditions. The establishment of the reinforcement scale database ensures the reusability of the reinforcement scale simulation results.

[0009] The database is used as a bridge to connect the component scale simulation and the reinforcement scale simulation. By providing the simulation data of the reinforcement scale to the database, it is convenient for the component scale to quickly obtain information such as the stiffness matrix and constitutive relationship through boundary conditions and material information. The preliminary results of the reinforcement scale simulation can also be stored in the database and applied to its subsequent deformation simulation without the need to simulate from the initial state. Using the database, different components of the same metal matrix composite material can use the calculation results of the same reinforcement scale simulation when performing component scale simulation, so that different units and integration points of the same component can share the same reinforcement scale simulation results, thereby greatly improving the reusability of the reinforcement scale simulation results. Using the database to connect the coupled simulation of the component scale and the reinforcement phase scale, rather than using the direct coupling of the component scale and the reinforcement scale, is the basis for ensuring the reusability of the reinforcement scale simulation and the efficiency of the dual-scale simulation calculation.

[0010] (2) Component scale simulation part.

[0011] This part is based on conventional finite element deformation simulation, and models the mold, billet and deformation parameters in the deformation process; unlike the conventional finite element method, in each incremental step, the unit and integration point data are extracted as keywords to query the reinforcement scale deformation information database; by querying the database, the stiffness matrix and constitutive relationship of each unit integration point of the component scale are obtained, and then this information can be used for the next incremental step calculation until the overall calculation is completed. The unit mesh type used in the component scale simulation can be a three-dimensional tetrahedral mesh, a hexahedral mesh, or a two-dimensional triangular or quadrilateral mesh. The invention does not limit the specific mesh type.

[0012] (3) Enhanced body-scale simulation.

[0013] Modeling and calculation are performed for specific material components and boundary conditions that are required by the component scale and are not available in the database, and calculation results such as equivalent stress and strain are obtained, and equivalent stiffness matrix and constitutive relationship are constructed. The modeling process includes the construction of representative volume elements, mechanical models and boundary constraints of materials.

[0014] When constructing a representative volume element model and mechanical model at the scale of metal matrix composite reinforcements, the method of constructing the representative volume element includes but is not limited to using 3D XRCT technology to obtain the reinforcement geometry and distribution of the real metal matrix composite, using a random insertion algorithm to obtain a virtual metal matrix composite, and using rigid body motion simulation to obtain a virtual metal matrix composite. The method of constructing the mechanical model includes but is not limited to using traditional mechanical properties characterization experiments and material parameters reported in literature.

[0015] The boundary conditions of the reinforcement scale simulation are determined by the database. When the database requires and there are no calculation results of a certain metal matrix composite material under specific boundary conditions, the reinforcement scale simulation part will be requested to establish corresponding representative volume elements and mechanical simulations, establish boundary conditions, perform finite element calculations, obtain calculation results and output them to the database to enrich and supplement the database.

[0016] When the enhanced body-scale simulation results have an inheritance relationship with the enhanced body simulation data contained in the database (that is, the required simulation results can be obtained by continuing to calculate based on the existing results without the need to calculate from the initial state), it is only necessary to read the data in the database and attach subsequent boundary constraints on this basis, thereby reducing the amount of calculation for the enhanced body-scale simulation.

[0017] The relationship between the three parts of component scale simulation, reinforcement scale simulation and database in the present invention is shown in the attached figure. Figure 1 As shown, the construction scale simulation obtains the constitutive relationship, stiffness matrix and other information it needs by querying the database. The database improves its own data through the simulation of the reinforcement scale. The reinforcement scale is simulated according to the component scale and the requirements of the database, and the required reinforcement scale simulation information is provided to the database for use in the component scale simulation.

[0018] The beneficial effects of the present invention are:

[0019] (1) The method of the present invention is used to achieve coupled simulation of the component scale and the reinforcement scale during the plastic processing of metal matrix composite components, so that the component scale deformation process is more in line with the actual situation. The reinforcement scale simulation can not only provide accuracy guarantee for the component scale simulation, but also make the simulation of its own scale deformation process more realistic. Through the dual-scale simulation of the large plastic deformation processing process of metal matrix composite components, it is possible to screen and optimize the mold and deformation process scheme, and reduce the trial and error cost of the metal matrix composite plastic processing process.

[0020] (2) The method of the present invention is used to establish a coupling connection between the reinforcement scale and the component scale through the database, instead of directly performing a calculation simulation of the reinforcement scale for each unit and integration point state, which can effectively improve the reusability of the reinforcement scale calculation results, thereby reducing the number of reinforcement scale simulations, reducing the calculation cost, and shortening the calculation time. In the database, even if there is no reinforcement scale calculation result under the target boundary condition, the calculation amount can be reduced by continuing the calculation by taking the model with the smallest difference from the target boundary condition in the existing calculation results as the initial state, instead of starting the calculation from the initial state, thereby further improving the calculation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of the process flow of the large deformation dual-scale coupled finite element simulation method for metal matrix composites.

[0022] Figure 2 Schematic diagram of component-scale simulation (extrusion process).

[0023] Figure 3 Representative volume element model at the reinforcement (particle) scale. DETAILED DESCRIPTION

[0024] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0025] Example 1

[0026] For the extrusion process of 17 vol.% SiCp / Al rods at 350°C, a billet and die model was established at the component scale to simulate the deformation and flow process from billet to rod, as shown in the attached figure. Figure 2 As shown; at the reinforcement scale, a representative volume element model of 17 vol.% SiCp / Al is established, as shown in the attached Figure 3 As shown in the figure, a reinforcement-scale mechanical model was established based on the mechanical properties reports of Al and SiC in the literature.

[0027] The stiffness matrix and constitutive relationship are set for the billet using the calculation results of the reinforcement scale in the initial state. During the deformation process, as the deformation continues, different parts of the bar and billet will have different stress and strain states. According to this state, the database is queried for information such as the stiffness matrix and constitutive relationship obtained by the reinforcement scale simulation in this state, thereby providing parameters for the next calculation. If the database does not have this information, a new calculation is performed using the reinforcement scale simulation (or the existing calculation is used as the initial state for continued calculation) to obtain the required data. After the simulation of the entire component scale is completed, the data in the database will be saved.

[0028] Using the simulation results, we obtained data on the flow, stress and strain in different regions of the component scale during the entire deformation process, providing guidance for optimizing mold and process design. The reinforcement scale simulation calculations performed in this process enriched the database and can continue to be used in the simulation of other plastic deformation processes of this material in the future.

[0029] Matters not covered by the present invention are known technologies.

[0030] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A dual-scale coupled finite element simulation method for metal matrix composite materials, characterized by: The method includes three parts: component scale simulation, database and reinforcement scale simulation. The simulation results of component scale and reinforcement scale are connected by using the database, so that the simulation results of reinforcement scale can be reused to reduce the calculation amount of dual-scale coupling simulation, thereby realizing efficient dual-scale coupling simulation of large plastic deformation process of metal matrix composite materials. The database part is as follows: The database stores the conditions and results of the reinforcement scale simulation calculation. Through the material component characteristics and boundary condition information, the equivalent stiffness matrix after deformation and the calculation results of the constitutive relationship reinforcement scale are queried; the database is used as a bridge to connect the component scale simulation and the reinforcement scale simulation; by providing the simulation information of the reinforcement scale to the database, it is convenient for the component scale to quickly obtain the stiffness matrix and constitutive relationship information through the boundary conditions and material information; the preliminary results of the reinforcement scale simulation are also stored in the database and applied to its subsequent deformation simulation without the need to simulate from the initial state; using the database, different components of the same metal matrix composite material use the same reinforcement scale simulation calculation results when performing component scale simulation, and different units and integration points of the same component share the same reinforcement scale simulation results, thereby greatly improving the reusability of the reinforcement scale simulation results; The component scale simulation part is to model the mold, billet and deformation parameters in the deformation process, extract the unit and integration point data in each incremental step, use it as the keyword to query the enhanced body scale deformation information database, and bring the query results into the unit and integration point for subsequent incremental step calculation; The reinforcement scale simulation part is to perform modeling and calculation on the material components and boundary conditions required by the component scale and not available in the database, obtain the equivalent stress-strain calculation results, and construct the equivalent stiffness matrix and constitutive relationship; The modeling process includes the construction of material representative volume elements, mechanical models and boundary constraints.

2. The dual-scale coupled finite element simulation method for metal matrix composite materials according to claim 1, characterized in that: This method uses coupled simulation of component scale and reinforcement phase scale to simulate the material flow and stress-strain evolution during large deformation of metal matrix composites. Analyze the influence of mold structure and deformation process parameters on component forming during large plastic deformation processing of metal matrix composite components, and optimize the mold and deformation process scheme.

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