A Modeling and Analysis Method for Crystalline Plasticity Finite Element Method of Metal Matrix Composites

Abstract

This invention discloses a modeling and analysis method for the finite element method of crystal plasticity in metal matrix composites, specifically relating to the field of aerospace metal matrix composites. The method includes: acquiring EBSD data of the metal matrix composite to be tested; identifying the metal matrix phase and reinforcing fiber phase based on the EBSD data; performing texture analysis on the metal matrix composite to determine grain orientation data; establishing a finite element model of the metal matrix composite to be tested based on the grain orientation data and generating a geometric mesh; identifying the metal matrix phase and reinforcing fiber phase in the finite element model and assigning parameters to each phase; determining the strain of the metal matrix composite to be tested based on a crystal plasticity constitutive model; and correcting the original crystal plasticity parameters based on the measured strain and strain to obtain the metal matrix composite model. The above metal matrix composite model can obtain the grain plastic strain during the plastic deformation process.

Description

Technical Field

[0001] This application relates to the field of metal matrix composites for aerospace applications, and in particular to a modeling and analysis method for the finite element method of crystal plasticity of metal matrix composites. Background Technology

[0002] With the rapid development of modern aerospace technology, key components of spacecraft will face extreme service environments such as high temperatures and high loads. This places demands on currently used alloys to meet the requirements for high temperature resistance, high strength, and lightweight properties. To meet these material requirements for spacecraft, metal matrix composites, represented by titanium matrix composites (TMCs), have improved the mechanical service performance (such as creep and fatigue) of traditional titanium alloys under high-temperature environments due to their in-situ generated spatial network reinforcing fibers (TiB). They are gradually replacing traditional titanium alloys. The load transfer efficiency and strain state exhibited by the reinforcing fibers (TiB) of TMCs during service are key factors determining the mechanical properties of TMCs under high-temperature environments. Only by deeply studying and predicting the microscopic stress-strain response of TMCs under external loads and quantifying the strengthening effect of the reinforcing fibers can we fully understand their failure and strengthening mechanisms, facilitating subsequent life prediction and process optimization.

[0003] However, conventional testing methods struggle to capture the microscopic stress-strain response of TMCs grains and reinforcing fibers under external loads, the slip system activation state, and the cumulative plastic strain change, making it difficult to quantify the reinforcing effect of the reinforcing fibers. Even in-situ EBSD and TEM testing methods can only obtain information about the local deformation of the material. Summary of the Invention

[0004] The main objective of this application is to provide a modeling and analysis method for the finite element method of crystal plasticity of metal matrix composites, which aims to solve the problem of difficulty in obtaining the grain plastic strain of metal matrix composites during plastic deformation.

[0005] To achieve the above objectives, this application provides a modeling method for the crystalline plasticity finite element method of metal matrix composites, comprising: acquiring EBSD data of the metal matrix composite to be tested, wherein the EBSD data includes Euler angles and phase numbers for each pixel; identifying the metal matrix phase and reinforcing fiber phase based on the EBSD data, and determining the Euler angles and phase numbers for each phase; performing texture analysis on the metal matrix composite to be tested to determine grain orientation data; establishing a finite element model of the metal matrix composite to be tested based on the grain orientation data, and generating a geometric mesh; identifying the metal matrix phase and reinforcing fiber phase in the finite element model based on the phase numbers; assigning crystal plasticity parameters to the metal matrix phase and elastic parameters to the reinforcing fiber phase; determining the strain of the metal matrix composite to be tested based on the crystal plasticity constitutive model and in combination with the crystal plasticity parameters and elastic parameters; acquiring the measured strain of the metal matrix composite to be tested, determining the corrected crystal plasticity parameters based on the measured strain to ensure that the strain is consistent with the measured strain; and replacing the crystal plasticity parameters with the corrected crystal plasticity parameters to obtain the metal matrix composite model.

[0006] Optionally, the identification of the metal matrix phase and the reinforcing fiber phase based on EBSD data includes: matching the preset crystallographic parameters of the metal matrix phase and the reinforcing fiber phase with EBSD data to identify the metal matrix phase and the reinforcing fiber phase; and determining the Euler angle and phase number of each phase accordingly, and storing the Euler angle, phase number, and name of each phase in a CSV file.

[0007] Optionally, texture analysis is performed on the metal matrix composite material to be tested to determine grain orientation data, including: grain aggregation of consecutive pixels by means of the orientation difference between adjacent pixels, and extraction of grain orientation data.

[0008] Optionally, based on the phase number, the metal matrix phase and the reinforcing fiber phase in the finite element model are identified; and crystal plasticity parameters are assigned to the metal matrix phase and elasticity parameters are assigned to the reinforcing fiber phase. This includes: obtaining the mesh node information of the geometric mesh, importing the mesh node information into the INP file corresponding to the finite element model; identifying the metal matrix phase and the reinforcing fiber phase in the INP file based on the CSV file, and assigning crystal plasticity parameters to the metal matrix phase and elasticity parameters to the reinforcing fiber phase in the INP file to obtain the updated INP file.

[0009] Optionally, the measured strain of the metal matrix composite material under test is obtained by conducting mechanical tests on the metal matrix composite material under test.

[0010] Optionally, the modified crystal plasticity parameter is determined based on the measured strain to ensure that the strain is consistent with the measured strain. This includes comparing the strain of the metal matrix composite material to be tested with the measured strain of the metal matrix composite material to be tested, adjusting the crystal plasticity parameter to ensure that the strain is consistent with the measured strain, and obtaining the modified crystal plasticity parameter.

[0011] Optionally, the crystal plasticity parameter is replaced by the modified crystal plasticity parameter to obtain the metal matrix composite model, including: replacing the crystal plasticity parameter in the INP file with the modified crystal plasticity parameter to obtain the Modified.inp file corresponding to the metal matrix composite model.

[0012] To achieve the above objectives, this application also provides an analytical method for the crystalline plasticity finite element method of metal matrix composites. The metal matrix composite model obtained by the above-mentioned modeling method includes: determining the cumulative plastic strain of the metal matrix composite model; constructing a metal material model, wherein the metal matrix material model does not contain reinforcing fiber phase, and determining the cumulative plastic strain of the metal material model; determining the fiber influence factor based on the cumulative plastic strain of the metal matrix composite model and the cumulative plastic strain of the metal material model; and analyzing the influence of fiber phase reinforcement on the mechanical behavior of the tested metal matrix composite based on the fiber influence factor.

[0013] Optionally, the fiber influence factor is determined based on the cumulative plastic strain of the metal matrix composite model and the cumulative plastic strain of the metal material model, including: determining the fiber influence factor based on the ratio of the difference between the cumulative plastic strain of the metal matrix composite model and the cumulative plastic strain of the metal material model to the cumulative plastic strain of the metal matrix composite model.

[0014] Optionally, the method for constructing a metallic material model includes replacing the material properties of the grains of the enhanced fibrous phase in the Modified.inp file with the material properties of the metallic matrix phase to obtain the metallic material model.

[0015] Compared with the prior art, the beneficial effects of this application are as follows:

[0016] The present invention provides a modeling and analysis method for the crystalline plasticity finite element method of metal matrix composites. Based on EBSD data, the method identifies the phases of the metal matrix composite under test, determines phase information, and performs texture analysis to determine grain orientation data. A finite element model is then established based on the grain orientation data, which maintains the true orientation and geometry of the metal matrix phase and the reinforcing fiber phase. Initial crystal plasticity and elastic parameters are assigned to the finite element model. By comparing the strain calculated by the crystal plasticity constitutive model with the measured strain from mechanical experiments, the crystal plasticity parameters are corrected based on the comparison results. This results in a metal matrix composite model capable of calculating the plastic deformation state of individual grains, the slip system activation state, and the cumulative plastic strain during the macroscopic deformation process of the metal matrix composite considering the interaction between the fibers and the metal matrix. A metal material model without the reinforcing fiber phase is constructed as a control model. The fiber influence factor is determined based on the cumulative plastic strain of the control model and the cumulative plastic strain of the metal matrix composite model. The fiber influence factor can quantitatively analyze the interaction relationship between the reinforcing fiber phase and the metal matrix phase, thereby quantifying the strengthening effect caused by the reinforcing fiber phase in the elastoplastic process of the alloy. Attached Figure Description

[0017] Figure 1 This is a schematic flowchart of the modeling method for the crystalline plasticity finite element method of metal matrix composites according to this application;

[0018] Figure 2 This is a schematic flowchart of the finite element method for analyzing the crystal plasticity of metal matrix composites according to this application;

[0019] Figure 3 The image shows the microstructure of the titanium-based composite material used in the example.

[0020] Figure 4 EBSD image of the titanium-based composite material in the example;

[0021] Figure 5 The finite element model of the titanium-based composite material in the example;

[0022] Figure 6 The strain calculation (LE) distribution cloud map of the titanium-based composite material in the example is shown.

[0023] Figure 7 A comparison of stress-strain curves from uniaxial tensile tests and finite element model calculations of the titanium-based composite material in the example.

[0024] Figure 8 The slip system strength distribution cloud map of the substrate slip system of the titanium-based composite material in the example;

[0025] Figure 9 The cumulative plastic strain distribution cloud map of the titanium-based composite material in the example is shown.

[0026] Figure 10 A comparison diagram of the cumulative plastic strain of a single grain of titanium-based composite material and titanium-based material in the example;

[0027] Figure 11 The graph shows the variation of fiber influence factors obtained from the titanium-based composite material model and the titanium-based material model, as an example.

[0028] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0030] The first embodiment of the present invention provides a modeling method for the crystalline plastic finite element method of metal matrix composites, such as... Figure 1 As shown, the specific steps include:

[0031] Step S1: Obtain the EBSD data of the metal matrix composite material to be tested. The EBSD data includes the Euler angle and phase number of each pixel.

[0032] Specifically, the metal matrix composite material to be tested was cut using wire electrical discharge machining (EDM) as the test specimen. First, the specimen was polished step-by-step using sandpaper with a grit size of 400#-2000#, ensuring the specimen maintained a uniform orientation throughout the polishing process to thoroughly remove surface scratches. Then, a vibratory polisher was used with a 0.2μm SiO2 polishing slurry to ensure a smooth surface without any deformation layer, resulting in the EBSD test specimen. An appropriate accelerating voltage (not less than 20KV) was set, and the scanning step size (not greater than 1 / 4 of the grain size) was set according to the grain size. EBSD data was acquired from the EBSD test specimen, resulting in a CTF file. The CTF file includes EBSD data, such as the Euler angles and phase numbers of each pixel.

[0033] Step S2: Identify the metal matrix phase and reinforcing fiber phase based on EBSD data, and determine the Euler angle and phase number of each phase;

[0034] Specifically, based on the preset phase numbers of the metal matrix phase and the reinforcing fiber phase, the data is matched with EBSD data to identify the metal matrix phase and the reinforcing fiber phase; the Euler angle and phase number of each phase are determined accordingly, and the Euler angle, phase number and name of each phase are stored in a CSV file and output as a CSV file.

[0035] Step S3: Perform texture analysis on the metal matrix composite material to be tested to determine grain orientation data;

[0036] Specifically, set the coordinate system convention, and the plotting coordinate system must be consistent with the EBSD observation coordinate system; select the study area in the format [XY dx dy], where X and Y are the selection origin, and dx and dy are the side lengths of the selected area along the x / y direction; aggregate continuous pixels in the CTF file into continuous grains by using the orientation difference between adjacent pixels, and extract the grain orientation data.

[0037] Step S4: Based on the grain orientation data, establish a finite element model of the metal matrix composite material to be tested and generate a geometric mesh;

[0038] It is worth noting that after establishing the finite element model of the metal matrix composite material to be tested, the corresponding INP file can be obtained. Subsequent finite element model processing is all completed by modifying the INP file. For example, the mesh type can be C3D8 or CPS4 elements, and the mesh size is selected according to the finite element model. It can be less than 1% of the shortest side of the finite element model to ensure the accuracy and convergence of the computational geometry mesh.

[0039] Step S5: Identify the metal matrix phase and reinforcing fiber phase in the finite element model according to the phase number; and assign crystal plasticity parameters to the metal matrix phase and elastic parameters to the reinforcing fiber phase; among which, crystal elastic parameters, grain orientation, rate correlation coefficient, reference shear strain rate, hardening modulus, saturation critical shear stress, initial critical shear stress, self-hardening coefficient and latent hardening coefficient are assigned.

[0040] Specifically, before recognition, it is necessary to check the Euler angle units in the CSV file, including radians and degrees. If the unit is degrees, it needs to be converted to radians.

[0041] Step S51: Obtain the mesh node information of the geometric mesh and import the mesh node information into the INP file corresponding to the finite element model;

[0042] Step S52: Identify the metal matrix phase and reinforcing fiber phase in the INP file based on the CSV file, and assign crystal plasticity parameters to the metal matrix phase and elastic parameters to the reinforcing fiber phase in the INP file, resulting in an updated INP file. Since the phase number of each phase has already been determined, i.e., whether each phase number belongs to the metal matrix phase or the reinforcing fiber phase has been determined, the metal matrix phase and the reinforcing fiber phase can be identified by matching the phase numbers in the CSV file with the phase numbers in the INP file.

[0043] Step S6: Determine the strain of the metal matrix composite material under test based on the crystal plastic constitutive model and in combination with the crystal plasticity and elasticity parameters; the expression for strain in the crystal plastic constitutive model is as follows:

[0044] (1);

[0045] In the formula, This represents the gradient of elastic deformation caused by grain distortion and rigid body rotation. This represents the deformation gradient that homogenizes the grains along the slip direction. It represents the deformation gradient tensor, which includes elastic strain and plastic strain.

[0046] Assuming during plasticity, the unit vector in the slip direction The unit vector of the slip surface normal constant. Indicates by The rotation tensor obtained from decomposition express The transpose of the crystal undergoes elastic distortion, potentially altering the lattice orientation and interatomic spacing. The evolving stress state within the material leads to reversible elastic deformation of the crystal structure, affecting its anisotropic mechanical response. Establishing the vectors in the current crystal configuration... and Compared with the unit vector in the initial crystal configuration and The relationship between the sliding system and the direction of the sliding system is shown in equations (2) and (3):

[0047] (2);

[0048] (3);

[0049] When performing the above finite element calculations on the mechanical properties of the metal matrix composite material to be tested, the corresponding load and displacement are used as boundary conditions.

[0050] Step S7: Obtain the measured strain of the metal matrix composite material to be tested, and determine the corrected crystal plasticity parameter based on the measured strain to make the strain consistent with the measured strain;

[0051] The measured strain is obtained through mechanical tests on the metal matrix composite material under test. These tests can include uniaxial tension, creep, and fatigue. Corrected crystal plasticity parameters include rate correlation coefficient, reference shear strain rate, hardening modulus, saturation critical shear stress, initial critical shear stress, self-hardening coefficient, and latent hardening coefficient.

[0052] Specifically, the strain of the metal matrix composite to be tested is compared with the measured strain of the metal matrix composite to be tested, and the crystal plasticity parameters are adjusted to make the strain consistent with the measured strain, thus obtaining the corrected crystal plasticity parameters.

[0053] Step S8: Replace the crystal plasticity parameter with the modified crystal plasticity parameter to obtain the metal matrix composite material model.

[0054] Specifically, the metal matrix phase and reinforcing fiber phase in the INP file are identified based on the CSV file. The crystal plasticity parameters in the INP file are then replaced using modified crystal plasticity parameters to obtain the Modified.inp file corresponding to the metal matrix composite model. After replacement, the parameter array length needs to be checked to ensure the correctness of the INP file. Once the metal matrix composite model is obtained, finite element analysis is performed to obtain the slip system strength and stress. The slip system strength reflects the plastic strain of the metal matrix composite, and the stress-strain curve can fully simulate the macroscopic stress-strain response of the metal matrix composite. The specific calculation formulas are as follows:

[0055] (4);

[0056] In the formula, Indicates the first The shear strain rate at which slip occurs in a slip system. This represents the plastic part of the velocity gradient tensor. Representing the There are 12 groups of slip systems for the FCC crystal structure and 30 groups for the HCP crystal structure. The unit vector in the direction of slip. It is the unit vector normal to the slip surface. The Schmid tensor is divided into symmetric parts. and the opposing part .

[0057] (5);

[0058] (6);

[0059] In continuum mechanics, the deformation gradient tensor It is an important mathematical tool for describing material deformation. It characterizes the relative displacement and deformation of each tiny volume element of an object during the deformation process. (Velocity gradient tensor) This is used to characterize the dynamic evolution of deformation. The velocity gradient tensor is defined as the rate of change of the deformation gradient with respect to time, and its derivative with respect to time t yields:

[0060] ;

[0061] In the formula, The elastic part of the velocity gradient tensor, i.e. ; The elastic part of the deformation gradient tensor. The plastic part of the deformation gradient tensor For the deformation gradient tensor The derivative of The plastic part of the velocity gradient tensor, i.e. .

[0062] It can also be decomposed into the tensor tensor. and rotation tensor ,Right now:

[0063] (8);

[0064] (9);

[0065] (10);

[0066] (11);

[0067] (12);

[0068] In the formula, This refers to the elastic portion of the stretch tensor. The plastic portion of the tensor tensor. The elastic part of the rotation tensor rate. The plastic component of the rotation tensor. for L transpose, for transpose, For the Schmid tensor, The symmetric part of the Schmid tensor For the antisymmetric part of the Schmid tensor, Indicates the first The shear strain rate when slip occurs in a slip system.

[0069] In crystalline materials, plastic deformation is primarily driven by dislocation motion. When the externally applied stress exceeds a certain critical value, i.e., reaches the critical shear stress of the slip system, dislocations are activated on specific slip surfaces and begin to move along the slip direction. This process marks the transition of the crystalline material from the elastic deformation stage to the irreversible plastic deformation stage. Using the rate-dependent flow criterion, the shear strain rate of the slip system... From critical decomposition shear stress and decompose shear stress Represented as:

[0070] (13);

[0071] In the formula, This represents the reference shear strain rate that affects the yield strength of the alloy. The brackets represent MaCaulay, and n represents the rate sensitivity coefficient when plastic flow occurs. The reference shear stress determines the ease with which the crystal can initiate a current slip, and is related to the current activation state of the slip system. This refers to the decomposition shear stress acting on the crystal.

[0072] (14);

[0073] In the formula, Represents the hardening matrix, when Time represents self-hardening, when Time represents latent hardening; Indicates the first The shear strain rate at which slip occurs in a slip system. Indicates the hardening rate. for The derivative;

[0074] (15);

[0075] (16);

[0076] In the formula, Indicates the hardening coefficient. Indicates the initial hardening modulus. Indicates the self-hardening modulus. Indicates saturated flow stress. This represents the initial shear stress at which the material begins to yield. This represents the sum of the cumulative plastic shear strain of all slip systems.

[0077] In plastic deformation theory, the concept of the Jaumann rate is typically introduced to reasonably describe the change of the stress tensor within a finite deformation framework. Since materials undergo extensive rotation and deformation during plastic deformation, the traditional definition of stress rate may be affected by rigid body rotation, leading to non-physical effects in numerical calculations. Therefore, the Jaumann rate, by introducing a covariant derivative, makes the evolution of the stress tensor independent of rigid body rotation, thus more accurately describing the stress evolution of materials under complex loading conditions. Dislocation motion only affects the plastic deformation of crystals and does not significantly affect the elastic response. Based on this characteristic, when establishing the elastic constitutive relation of materials, the influence of dislocation motion on the elastic properties of crystals can be ignored, and the elastic constitutive relation of materials can be directly derived based on continuum mechanics and elasticity theory. Furthermore, within the framework of the Jaumann rate, the rate of stress evolution is obtained through the following relationship:

[0078] (17);

[0079] In the formula, Cauchy stress tensor The Jaumann rate (elastic part). For stress evolution rate, Let be the elastic tensor of the crystal. This refers to the elastic portion of the stretch tensor. This is the elastic part of the rotation tensor.

[0080] Therefore, when considering both the elastoplastic deformation of the crystal, equation (17) is replaced by the Jaumann derivative of the Cauchy stress tensor based on the initial crystal configuration, i.e.

[0081] (18);

[0082] In the formula, Cauchy stress tensor Jaumann, For the rotation tensor rate, This represents the stress evolution rate.

[0083] Subtracting (18) from equation (17) gives:

[0084] (19);

[0085] (20);

[0086] Substituting into equation (12), we get:

[0087] (twenty one);

[0088] Combining equations (18) and (21), in the crystal plastic constitutive model of a single grain, the stress is expressed as:

[0089] (twenty two);

[0090] Then, from equation (9), we get:

[0091] (twenty three);

[0092] Substituting into equation (11), we obtain the stress response during crystal deformation:

[0093] (twenty four);

[0094] In the formula, The symmetric part of the Schmid tensor , For the antisymmetric part of the Schmid tensor, For the first The shear strain rate at which slip occurs in a slip system. Let be the elastic tensor of the crystal. For the stretch tensor, For Cauchy stress tensor, This refers to the elastic portion of the stretch tensor. The plastic portion of the tensor tensor. This is the plastic component of the rotational tensor.

[0095] The stress during crystal deformation can be obtained by formula (24), thereby enabling the capture of the micro-stress-strain response of the grains and reinforcing fibers of metal matrix composites under external load.

[0096] The second embodiment of the present invention provides a finite element method for analyzing the crystal plasticity of metal matrix composites, using the aforementioned metal matrix composite model, such as... Figure 2 As shown, it includes:

[0097] Step S9, determine the cumulative plastic strain of the metal matrix composite model, expressed as:

[0098] (25);

[0099] Step S10: Construct a metallic material model. The metallic matrix material model does not contain the reinforcing fiber phase. Determine the cumulative plastic strain of the metallic material model.

[0100] Specifically, the material properties of the enhanced fibrous phase grains in the Modified.inp file are replaced with the material properties of the metallic matrix phase to obtain the metallic material model;

[0101] Step S11: Determine the fiber influence factor based on the cumulative plastic strain of the metal matrix composite model and the cumulative plastic strain of the metal material model.

[0102] Specifically, the fiber influence factor is determined based on the ratio of the difference between the cumulative plastic strain of the metal matrix composite model and the cumulative plastic strain of the metal material model to the cumulative plastic strain of the metal matrix composite model. The expression is:

[0103] (26);

[0104] In the formula, This represents the cumulative plastic strain in the metal matrix composite model. This represents the cumulative plastic strain in a metallic material model.

[0105] Step S12: Analyze the influence of the reinforcing fiber phase on the mechanical behavior of the tested metal matrix composite material based on the fiber influence factor.

[0106] In this embodiment, phase identification and determination of phase information are performed on the tested metal matrix composite material based on EBSD data. Texture analysis is then conducted to determine grain orientation data. A finite element model is established based on this grain orientation data, which maintains the true orientation and geometry of the metal matrix phase and the reinforcing fiber phase. Initial crystal plasticity and elastic parameters are assigned to the finite element model. By comparing the strain calculated by the crystal plasticity constitutive model with the measured strain from mechanical experiments, the crystal plasticity parameters are corrected based on the comparison results. The resulting metal matrix composite model can calculate the plastic deformation state of individual grains, the slip system activation state, and the cumulative plastic strain during the macroscopic deformation process of the metal matrix composite material considering the interaction between the fibers and the metal matrix. A metal material model without the reinforcing fiber phase is constructed as a control model. The fiber influence factor is determined based on the cumulative plastic strain of the control model and the cumulative plastic strain of the metal matrix composite model. The fiber influence factor can quantitatively analyze the interaction relationship between the reinforcing fiber phase and the metal matrix phase.

[0107] Example

[0108] Finite element modeling and analysis were performed on titanium-based composite materials, and the microstructure of the titanium-based composite materials is as follows: Figure 3 As shown, the titanium-based composite material is composed of a metallic matrix phase TA15 and a reinforcing fiber phase TiB, with the reinforcing fiber phase being uniformly distributed within the alloy matrix.

[0109] In step S100, titanium-based composite materials were cut as test specimens using wire electrical discharge machining (EDM). The test specimens were then polished stepwise with sandpaper of grit sizes ranging from 400# to 2000#, with each polishing time lasting 15 minutes. A Buehler vibratory polisher was then used with 0.2μm SiO2 polishing liquid for 2 hours to obtain EBSD test specimens. A ZEISS Sigma300 scanning electron microscope (equipped with an EDAX EBSD probe) was used with an accelerating voltage of 20KV and a scanning step size of 0.35μm to acquire EBSD data and obtain CTF files from the EBSD test specimens.

[0110] Step S200: Identify the metal matrix phase and reinforcing fiber phase based on EBSD data. The TA15 matrix has a Ti-Hex crystal structure, which includes a base slip system, a cylindrical slip system, a first-order pyramidal slip system, and a second-order pyramidal slip system. TiB has an orthorhombic crystal structure. Since TiB only undergoes elastic deformation during stretching, plastic deformation of TiB is not considered. Set the drawing coordinate system to be consistent with the EBSD observation coordinate system. In this coordinate system, use a 10° orientation difference as the grain boundary identification threshold, aggregate adjacent pixels as continuous grains, and extract grain orientation data. EBSD data (image) can be found here. Figure 4 ,right Figure 4 A local magnification of 'a' is obtained Figure 4 b, get Figure 4 The grain boundary coordinates of the metallic matrix phase and the reinforcing fiber phase in b are shown in [reference]. Figure 4 In the middle c, the grain boundaries between the metal matrix phase and the reinforcing fiber phase are captured.

[0111] Step S300: Based on the grain orientation data, establish a finite element model of the titanium-based composite material and generate a geometric mesh, see... Figure 5 The mesh size is 1μm and the mesh type is CPS4.

[0112] Step S400: Identify the metal matrix phase and reinforcing fiber phase in the finite element model according to the phase number; and assign crystal plasticity parameters to the metal matrix phase and elastic parameters to the reinforcing fiber phase.

[0113] Step S500: A high-temperature uniaxial tensile test is performed on the titanium-based composite material at a temperature of 600℃ and a tensile rate of 1e-3s. -1 The measured strain of the titanium-based composite material was obtained through testing. The experimental conditions were used as boundary conditions for the finite element model. Based on the crystal plastic constitutive model and combined with crystal plastic and elastic parameters, the strain of the titanium-based composite material was determined. (See...) Figure 6As can be seen from the strain distribution cloud map, the true strain of the titanium matrix composite material is mainly distributed in the metal matrix during the microstructural deformation process, while the deformation of the reinforcing fibers is relatively small. This corresponds to the strengthening effect of the reinforcing fiber phase in the actual service process of the titanium matrix composite material. A comparison between the stress-strain curves calculated by finite element method and the stress-strain curves obtained experimentally is shown in [Figure number missing]. Figure 7 This demonstrates that the modeling method in this embodiment can fully simulate the macroscopic stress-strain response of titanium-based composite materials.

[0114] In step S600, based on the measured strain of the titanium-based composite material, the rate correlation coefficient, reference shear strain rate, hardening modulus, saturation critical shear stress, initial critical shear stress, self-hardening coefficient, and latent hardening coefficient are all adjusted to ensure that the strain of the titanium-based composite material is consistent with the measured strain, thereby obtaining the corrected crystal plasticity parameters.

[0115] Step S700: Identify the metallic matrix phase and reinforcing fiber phase in the finite element model according to the phase number; replace the crystal plasticity parameter with the corrected crystal plasticity parameter to obtain the titanium-based composite material model. Perform finite element calculations on the titanium-based composite material model to obtain the slip system strength. Figure 8 The slip system strength distribution cloud map shows that the slip strength of the alloy matrix at the location with the fiber-reinforced phase is lower. This indicates that the slip system around the reinforcing fiber is not fully activated during the deformation of the titanium-based composite material, further demonstrating the inhibitory effect of the reinforcing fiber on the microscopic plastic deformation of the alloy.

[0116] Step S800: Determine the cumulative plastic strain of the titanium-based composite model (including fiber-reinforced RVE). The cumulative plastic strain distribution cloud map is shown below. Figure 9 It can be seen that the slip strength of the alloy matrix with the fiber-reinforcing phase is lower, which indicates that the slip system around the reinforcing fiber is not fully activated during the deformation of the titanium-based composite material, further demonstrating the role of the reinforcing fiber phase. Figure 7-9 Both studies demonstrate the inhibitory effect of reinforcing fibers on the microscopic plastic deformation of the alloy. The material properties of the reinforcing fiber phase TiB in the titanium matrix composite model were replaced with those of the metallic matrix phase TA15 to obtain the titanium matrix material model (RVE without reinforcing fibers). The cumulative plastic strain of the titanium matrix material model was then determined, and the results of the two studies are compared below. Figure 10 , Figure 10 In the diagram, 'a' represents the cumulative plastic strain diagram of a single grain (TA15-TiBw) in the titanium-based composite material. Figure 10 In the diagram, b represents the cumulative plastic strain diagram of a single grain (TA15) of the titanium-based material. Figure 10 a and Figure 10 The cloud map calculation results for b are shown below. Figure 10In Figure c, by comparing and analyzing the two models, it can be seen from the figure that under the same macroscopic deformation and at the same spatial location, the cumulative plastic strain field distribution shows that the TiB reinforcing fiber in the titanium matrix composite model can introduce significant strain incompatibility. This forces the surrounding matrix to coordinate deformation by localizing and repeatedly activating multiple slip systems. Therefore, the plastic deformation in TiBw / TA15 exhibits stronger non-uniformity and concentration.

[0117] Step S900: Based on the cumulative plastic strain of the titanium-based composite material model and the cumulative plastic strain of the titanium-based material model, determine the fiber influence factor, see [link to relevant documentation]. Figure 11 As shown in the figure, the fiber reinforcement factor can quantitatively characterize the additional plastic compatibility behavior introduced by TiB reinforcing fibers during deformation. Unlike traditional strengthening parameters based on stress or stiffness, the fiber reinforcement factor directly reflects the degree of cumulative slip activity required to maintain strain compatibility. In the initial stage of strain induction in the titanium matrix composite, the reinforcing fiber phase and the matrix mainly undergo elastic co-deformation, with the high stiffness of the reinforcing fiber phase sharing part of the load and delaying the initiation of matrix slip. As the strain of the titanium matrix composite increases, the fiber reinforcement factor shows a monotonically increasing trend, indicating that the TiB fibers gradually exacerbate the non-uniformity of material deformation, forcing the matrix to coordinate macroscopic deformation through localization and repeated activation of the slip system. Therefore, the fiber reinforcement factor can be regarded as an index of plastic efficiency loss caused by strain incompatibility induced by the reinforcing phase, establishing a clear physical link between the slip transmission obstruction observed in experiments and the cumulative plastic strain enhancement predicted by crystal plasticity simulation.

[0118] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A modeling method for the crystalline plasticity finite element method of metal matrix composites, characterized in that, include: Obtain EBSD data of the metal matrix composite material under test. The EBSD data includes the Euler angle and phase number of each pixel. Identify the metal matrix phase and reinforcing fiber phase based on EBSD data, and determine the Euler angle and phase number of each phase; Texture analysis was performed on the metal matrix composite material under test to determine grain orientation data; Based on the grain orientation data, a finite element model of the metal matrix composite material under test is established, and a geometric mesh is generated. Based on the phase number, the metal matrix phase and the reinforcing fiber phase in the finite element model are identified; and crystal plasticity parameters are assigned to the metal matrix phase and elasticity parameters are assigned to the reinforcing fiber phase. The strain of the metal matrix composite material under test is determined based on the crystal plastic constitutive model and in combination with the crystal plastic parameters and elastic parameters. The measured strain of the metal matrix composite material to be tested is obtained, and the corrected crystal plasticity parameters are determined based on the measured strain to make the strain consistent with the measured strain. By replacing the crystal plasticity parameter with the modified crystal plasticity parameter, a metal matrix composite model is obtained.

2. The modeling method for the finite element method of crystal plasticity of metal matrix composites according to claim 1, characterized in that, The metal matrix phase and reinforcing fiber phase were identified based on EBSD data, including: Based on the preset crystallographic parameters of the metal matrix phase and the reinforcing fiber phase, the data is matched with EBSD data to identify the metal matrix phase and the reinforcing fiber phase; and the Euler angle and phase number of each phase are determined accordingly, and the Euler angle, phase number and name of each phase are stored in a CSV file.

3. The modeling method for the crystalline plasticity finite element method of metal matrix composites according to claim 1, characterized in that, Texture analysis was performed on the metal matrix composite material under test to determine grain orientation data, including: Grain aggregation is performed on consecutive pixels based on the orientation difference between adjacent pixels, and grain orientation data is extracted.

4. The modeling method for the crystalline plasticity finite element method of metal matrix composites according to claim 1, characterized in that, Identify the metal matrix phase and reinforcing fiber phase in the finite element model based on the phase number; And it imparts crystal plasticity parameters to the metal matrix phase and elastic parameters to the reinforcing fiber phase, including: Obtain the mesh node information of the geometric mesh and import the mesh node information into the INP file corresponding to the finite element model; Identify the metal matrix phase and reinforcing fiber phase in the INP file based on the CSV file, and assign crystal plasticity parameters to the metal matrix phase and elasticity parameters to the reinforcing fiber phase in the INP file to obtain the updated INP file.

5. The modeling method for the crystalline plasticity finite element method of metal matrix composites according to claim 1, characterized in that, The measured strain of the metal matrix composite material under test is obtained by conducting mechanical tests on the metal matrix composite material under test.

6. The modeling method for the finite element method of crystal plasticity of metal matrix composites according to claim 1, characterized in that, The corrected crystal plasticity parameters are determined based on the measured strain to ensure that the strain matches the measured strain, including: The strain of the metal matrix composite to be tested is compared with the measured strain of the metal matrix composite to be tested, and the crystal plasticity parameter is adjusted to make the strain consistent with the measured strain, thus obtaining the corrected crystal plasticity parameter.

7. The modeling method for the finite element method of crystal plasticity of metal matrix composites according to claim 1, characterized in that, By replacing the crystal plasticity parameter with a modified crystal plasticity parameter, a metal matrix composite model is obtained, including: The modified crystal plasticity parameters in the INP file are replaced by the modified crystal plasticity parameters to obtain the Modified.inp file corresponding to the metal matrix composite model.

8. A finite element method for analyzing the crystalline plasticity of metal matrix composites, characterized in that, The metal matrix composite model obtained by the modeling method of the crystalline plastic finite element method for metal matrix composites according to any one of claims 1-7 includes: Determine the cumulative plastic strain of the metal matrix composite model; Construct a metallic material model, which does not contain reinforcing fiber phases, and determine the cumulative plastic strain of the metallic material model; The fiber influence factor is determined based on the cumulative plastic strain of the metal matrix composite model and the cumulative plastic strain of the metal material model. The influence of fiber phase reinforcement on the mechanical behavior of the tested metal matrix composite material was analyzed based on the fiber influence factor analysis.

9. The finite element method for analyzing the crystal plasticity of metal matrix composites according to claim 8, characterized in that, Based on the cumulative plastic strain of the metal matrix composite model and the cumulative plastic strain of the metal material model, the fiber influence factor is determined, including: The fiber influence factor is determined by the ratio of the difference between the cumulative plastic strain of the metal matrix composite model and the cumulative plastic strain of the metal material model to the cumulative plastic strain of the metal matrix composite model.

10. The finite element method for analyzing the crystal plasticity of metal matrix composites according to claim 8, characterized in that, Methods for constructing models of metallic materials include: Replace the material properties of the enhanced fibrous phase grains in the Modified.inp file with the material properties of the metallic matrix phase to obtain the metallic material model.

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