Calculation method for contact magnetoelectric coupling variable of piezoelectric matrix containing piezomagnetic particles

Abstract

The invention discloses a method for calculating a contact magnetoelectric coupling variable of a piezoelectric matrix containing piezomagnetic particles, belongs to the field of contact application of novel magnetoelectric functional devices, and comprises a general model for realizing functional attributes of MEE composite materials in a contact loading mode. Taking a force load to load a contact model on an MEE composite material containing a piezomagnetic particle piezoelectric matrix as an example, according to a piezomagnetic phase and piezoelectric phase constitutive model and a multi-physics field coupling theory, a finite element numerical simulation method is adopted, and a mechanism for regulating and controlling a magnetoelectric coupling variable through the force load is systematically disclosed.

Description

Technical Field

[0001] The present invention belongs to the field of contact applications of novel magnetoelectric functional devices, and particularly relates to a calculation method for the magnetoelectric coupling variables of a piezoelectric matrix containing piezomagnetic particles in contact. Background Art

[0002] Piezoelectric-magnetostrictive (MEE) multiferroic composites have broad application prospects in the fields of realizing high-capacity disk memories, nanogenerators, contact magnetoelectric sensors, etc. The above applications are all realized through contact. Therefore, there is an urgent need to develop a calculation model suitable for solving how MEE composites adjust magnetoelectric coupling variables under contact, or in other words, a calculation model for the variation law of magnetoelectric coupling variables during the contact process of MEE composites.

[0003] Existing contact models for piezoelectric-magnetostrictive multiferroic composites often neglect the microstructure of MEE composites. However, in fact, the contact performance of MEE composites is closely related to their microstructure. Therefore, existing models are only limited to solving the macroscopic manifestation of magneto-electro-elastic energy during the contact process of MEE composites, and lack research on the internal mechanism of how MEE materials adjust the force-magnetism-electricity conversion through contact.

[0004] Patent CN118228550A proposes a calculation method for the magnetoelectric coefficient of a multilayer nonlinear magnetostrictive-piezoelectric composite material. This method for directly calculating the magnetoelectric conversion coefficient by magnetically driving MEE materials is more inclined to applications in the fields of magnetoelectric sensors, magnetoelectric energy storage devices, electromagnetic antennas, etc. Although it is stated in the article that the results are applicable to the MEE composite contact model, obviously, it is more reasonable to directly establish an MEE composite contact model to solve the magnetoelectric coupling variables. Summary of the Invention

[0005] To solve the above technical problems, the present invention provides a calculation method for the magnetoelectric coupling variables of a piezoelectric matrix containing piezomagnetic particles in contact, including:

[0006] Simplify the actual contact situation of the composite material into a contact model of a rigid indenter and a half-space MEE composite material;

[0007] According to the MEE composite contact model, establish a force-magnetism coupling constitutive model, and solve the magnetic and mechanical physical quantities during the contact process of the piezomagnetic phase according to the elastic field, magnetic field control equations and magnetic and mechanical boundaries;

[0008] According to the MEE composite contact model, establish a force-electricity coupling constitutive model, and solve the electrical and mechanical physical quantities during the contact process of the piezoelectric phase according to the elastic field, electric field control equations and electrical and mechanical boundaries;

[0009] Based on the solutions of the magnetic physical quantities and mechanical physical quantities and the solutions of the electrical physical quantities and mechanical physical quantities, a contact geometry model of piezomagnetic particle-piezoelectric matrix composite considering the microstructure is established;

[0010] The contact geometry model of piezomagnetic particle-piezoelectric matrix composite considering the microstructure is discretized, and at the same time, the material properties of the discretized piezomagnetic particle-piezoelectric matrix composite geometry model are assigned;

[0011] Loads are applied to the model with assigned material properties, the finite element numerical model is solved, and post-processing is carried out to obtain magnetoelectric coupling variables.

[0012] Preferably, the process of simplifying the actual contact situation of the composite material into a contact model of a rigid contact indenter and a half-space MEE composite material includes:

[0013] Taking the contact point of the rigid indenter and the half-space MEE composite material as the coordinate origin, a rectangular coordinate system is established. The rigid indenter contacts the MEE composite material under the action of longitudinal load and transverse load, and the contact model of the rigid contact indenter and the half-space MEE composite material is constructed.

[0014] Preferably, the process of completing the solution of the magnetic physical quantities and mechanical physical quantities during the piezomagnetic phase contact process includes:

[0015] Based on the linear force-magnetic coupling relationship, a force-magnetic coupling constitutive model is constructed;

[0016] Substitute the elastic field, magnetic field control equations and magnetic and mechanical boundary conditions into the force-magnetic coupling constitutive model to complete the solution of the magnetic physical quantities and mechanical physical quantities during the piezomagnetic phase contact process.

[0017] Preferably, the process of completing the solution of the electrical physical quantities and mechanical physical quantities during the piezoelectric phase contact process includes:

[0018] Based on the linear force-electric coupling relationship, a force-electric coupling constitutive model is constructed;

[0019] Substitute the elastic field, magnetic field control equations and electrical and mechanical boundary conditions into the force-electric coupling constitutive model to complete the solution of the electrical physical quantities and mechanical physical quantities during the piezoelectric phase contact process.

[0020] Preferably, the Voigt form of the force-magnetic coupling constitutive model can be expressed as:

[0021] ;

[0022] Where 、 、 、 、 、 Represents the piezomagnetic stress, , , Represents the magnetic field strength, , , Represents the magnetic flux, , , , , , Represents the piezomagnetic strain, Represents the elastic coefficient of the piezomagnetic material, Represents the piezomagnetic coupling coefficient, Represents the magnetic permeability.

[0023] The expressions of the elastic field, magnetic field control equations and magnetic and mechanical boundary conditions are:

[0024] ;

[0025] In the formula , , , , , Represents the piezomagnetic stress, , , , , , Represents the piezomagnetic strain, , , Represents the magnetic flux, , , Represents the magnetic flux density, Represents the magnetic potential at the grid node, Represents the displacement component at the piezomagnetic phase grid node, " " is the partial differential symbol.

[0026] Preferably, the Voigt form of the force - electric coupling constitutive model can be expressed as:

[0027] ;

[0028] Among them, , , , , , Represents the piezoelectric stress, , , represents the electric field strength, , , represents the electric displacement, , , , , represents the piezoelectric strain, represents the elastic coefficient of the piezomagnetic material, represents the piezoelectric coupling coefficient, represents the conductivity.

[0029] The expression of the elastic field, electric field control equation and electrical and mechanical boundary conditions is:

[0030] ;

[0031] In the formula , , , , , represents the piezoelectric stress, , , , , represents the piezoelectric strain, , , represents the electric displacement, , , represents the electric field strength, represents the electric potential at the grid node, represents the displacement component at the piezoelectric phase grid node, " " represents the partial differential symbol.

[0032] Preferably, for the piezomagnetic particle - piezoelectric matrix composite material considering the microstructure: the radius of the piezomagnetic particles follows a normal distribution, and the ratio with the piezoelectric matrix is expressed as:

[0033] ;

[0034] In the formula, represents the volume fraction of the piezomagnetic particles, represents the side length of a certain cubic sampling interval, represents the radius of a certain piezomagnetic particle within the sampling interval, represents the number of the piezomagnetic particle.

[0035] Preferably, the model material properties include: the stiffness coefficient, piezoelectric coupling coefficient, and dielectric constant of the piezoelectric material, and the elastic coefficient, piezomagnetic coupling coefficient, and magnetic permeability of the piezomagnetic material.

[0036] Preferably, the loads include: longitudinal load, transverse load, electrical load, and magnetic load, and the loads within the contact area are:

[0037] ;

[0038] where represents the corresponding stress component of the matrix (i = m, p), represents the tangential force of the grid node within the contact area, the normal force of the grid node within the contact area, represents the total tangential load, represents the total normal load, represents the electric displacement component, represents the magnetic flux component, g represents the electrical load, and q represents the magnetic load.

[0039] On the other hand, the present invention also provides a computer-readable storage medium storing a computer program, and when the computer program is executed by a processor, the method is implemented.

[0040] Compared with the prior art, the present invention has the following advantages and technical effects:

[0041] The present invention establishes a general model for realizing the functional properties of MEE composites through contact action. Taking the MEE composite of a piezoelectric matrix containing piezomagnetic particles as an example, through the multi-physical field coupling theory and the finite element numerical simulation method, the regulation mechanism of force load on the magnetoelectric coupling variables is systematically revealed.

[0042] Its characteristics lie in considering the micro-structure of the MEE composite (such as the piezomagnetic particle size r and volume fraction vf) and the macroscopic contact parameters (the indenter radius R, the indentation amount ω, and the regulation parameters of the actual working conditions during the contact process of the MEE composite), and combining the constitutive equations of the piezoelectric phase and piezomagnetic phase with the actual working condition boundaries, successfully realizing the prediction of the objective law of the regulation of magnetoelectric coupling variables by force load. Objective law prediction. Description of the Drawings

[0043] The drawings constituting a part of this application are used to provide a further understanding of this application. The schematic embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation to this application. In the drawings:

[0044] Figure 1Schematic diagram of the contact model of the MEE (0-3 type) composite material according to an embodiment of the present invention;

[0045] Figure 2 Schematic diagram of the probability distribution of the piezomagnetic particle size according to an embodiment of the present invention;

[0046] Figure 3 Schematic diagram of the contact geometry model of the MEE (0-3) type composite material according to an embodiment of the present invention;

[0047] Figure 4 Schematic diagram of the contact discrete model of the MEE (0-3) type composite material according to an embodiment of the present invention;

[0048] Figure 5 FEM solution results of the x-z section along the negative z-axis under the contact action of the MEE composite material (0-3 type) according to an embodiment of the present invention, (a) von Mises stress, (b) electric potential φ, (c) electric field normE, (d) magnetic flux normB;

[0049] Figure 6 FEM solution results of the contact surface under the contact action of the MEE composite material (0-3 type) according to an embodiment of the present invention, (a) contact pressure pm, (b) electric potential φ, (c) magnetic field Hz;

[0050] Figure 7 For each parameter of the embodiment of the present invention on the magnetoelectric coefficient component Schematic diagram, where (a), radius of the piezomagnetic particle, (b), volume fraction of the piezomagnetic particle, (c), radius of the indenter;

[0051] Figure 8 For each parameter of the embodiment of the present invention on the magnetoelectric coefficient component Schematic diagram, where (a), radius of the piezomagnetic particle, (b), volume fraction of the piezomagnetic particle, (c), radius of the indenter; Detailed implementation manners

[0052] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments may be combined with each other. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0053] It should be noted that the attached drawings illustrate a case of solving the magnetoelectric coupling variables of the longitudinal load loading contact mechanics model of the piezomagnetic particle-containing piezoelectric matrix considering the microstructure. This method is also applicable to piezoelectric particle-piezomagnetic matrix, piezomagnetic fiber (piezoelectric fiber) - piezoelectric matrix (piezomagnetic matrix) and any shape particle-matrix composite material structure types; at the same time, it is not limited to the independent longitudinal load loading method, but also applicable to the solution of magnetoelectric coupling variables for transverse load, magnetic load, electric load independent and combined loading methods.

[0054] Example 1

[0055] In this embodiment, a calculation method for the magnetoelectric coupling variable of a piezoelectric matrix containing piezomagnetic particles is provided, including:

[0056] Simplify the actual contact situation of the composite material into a contact model of a rigid indenter and a half-space MEE composite material;

[0057] According to the MEE composite material contact model, establish a force-magnetic coupling constitutive model, and solve the magnetic and mechanical physical quantities during the contact process of the piezomagnetic phase according to the elastic field, magnetic field control equations, and magnetic and mechanical boundaries;

[0058] According to the MEE composite material contact model, establish a force-electric coupling constitutive model, and solve the electrical and mechanical physical quantities during the contact process of the piezoelectric phase according to the elastic field, electric field control equations, and electrical and mechanical boundaries;

[0059] Based on the solution processes of the magnetic and mechanical physical quantities and the solution processes of the electrical and mechanical physical quantities, establish a contact geometry model of a piezomagnetic particle-piezoelectric matrix composite material considering the microstructure;

[0060] Discretize the contact geometry model of the piezomagnetic particle-piezoelectric matrix composite material considering the microstructure, and at the same time endow the discretized piezomagnetic particle-piezoelectric matrix composite material geometry model with material properties;

[0061] Apply a load to the model after endowing it with material properties, complete the solution of the finite element numerical model, perform post-processing, and obtain the magnetoelectric coupling variable.

[0062] Establishment of the mechanical model:

[0063] There are many application fields for realizing the functional properties of MEE composite materials through contact, but the contact area is always a local action. Therefore, a general contact model for MEE composite materials can be established to calculate the magnetoelectric coupling variables during the contact process of MEE composite materials. Simplify the actual contact situation of the composite material into a contact model of a rigid contact indenter (four types of indenters: insulating indenter / PE indenter / FE indenter / MEE indenter) and a half-space MEE composite material. The rigid indenter plays a role in the transfer of force load, electric load, and magnetic load during the actual contact process of the MEE composite material. Under the action of the force load, the regulation of the magnetoelectric coupling variable can be realized through contact.

[0064] Such as Figure 1As shown in the figure, a contact theory model considering the microstructure of MEE composite materials (piezomagnetic particles - piezoelectric matrix) is considered. The matrix is the piezoelectric (PE) phase, and the particle phase is the piezomagnetic phase (PM). Taking the contact point between the rigid indenter and the half - space MEE composite material as the origin of the coordinate system, a rectangular coordinate system is established. The radius of the indenter is R. Under the action of the longitudinal load Pz and the transverse load Px, it contacts the MEE composite material (if the indenter is made of PE material, the electrical load g needs to be considered; if it is made of PM material, the magnetic load q needs to be considered; if it is made of MEE material, both the electrical load g and the magnetic load q need to be considered simultaneously). It is considered that the electrical potential (magnetic potential) at infinity of the substrate is grounded.

[0065] Distribution of piezomagnetic particles in the piezoelectric matrix:

[0066] The piezomagnetic particle - piezoelectric matrix composite material was prepared by sol - gel method experiments. The cross - section of the MEE composite material was observed by Aspex scanning electron microscope, and the distribution of piezomagnetic particles in the piezoelectric matrix and the particle size probability distribution were obtained. As Figure 2 shown, the particle size probability distribution of piezomagnetic particles conforms to the normal distribution. The ratio of piezomagnetic particles to the piezoelectric matrix can be defined as:

[0067] ;

[0068] In the formula, represents the volume fraction of piezomagnetic particles, represents the side length of a certain cubic sampling interval, represents the radius of a certain piezomagnetic particle in the sampling interval, represents the number of the piezomagnetic particle.

[0069] Magnetoelectric coupling variables of the MEE composite material contact model:

[0070] Process of force load regulating magnetoelectric coupling variables: When the force load acts on the rigid indenter, the force load is transmitted through the contact action; through the force - electricity coupling property of the piezoelectric phase (PE), the force - electricity conversion is realized, and the induced electric potential is generated; through the transfer of the interfacial stress / strain between the piezoelectric matrix and the piezomagnetic particles, the conversion of the induced electric potential and the magnetic potential is realized, that is, magnetoelectric coupling. The magnetoelectric coupling effect in the contact process of MEE composite materials is usually measured by the magnetoelectric coupling variable and can be expressed as:

[0071] ;

[0072] In the formula, and are the electric field components of the PE phase and the magnetic field components of the PM phase in the contact area of the MEE composite material respectively. The MEE composite material is a transversely isotropic material. According to the properties of transversely isotropic materials: i = j, (i = 1, 2, 3). If the xoy plane is a transversely isotropic plane, then there is When At that time, In the subsequent steps, the contact model of MEE composite materials will be established by finite element numerical simulation, and the magnetoelectric coupling variables , The specific process.

[0073] Finite element model solution process:

[0074] Considering that the solution of the MEE composite material contact model problem belongs to a multi-physical field coupling problem (magnetic field, electric field, elastic field and their coupling effects), and at the same time has strong boundary effects and size effects, a finite element numerical simulation program is written for solution. The specific steps are as follows:

[0075] (1) Establish a force-magnetic coupling constitutive model to complete the solution of magnetic and mechanical physical quantities during the contact process of the PM phase. Here, a linear piezomagnetic constitutive model is adopted. To complete the solution of the linear piezomagnetic constitutive model, the control equations of the magnetic field and elastic field and the corresponding magnetic field boundaries and mechanical boundaries need to be introduced;

[0076] (2) Establish a force-electric coupling constitutive model to complete the solution of electrical and mechanical physical quantities during the contact process of the PE phase. Here, a linear piezoelectric constitutive model is adopted. To complete the solution of the piezoelectric constitutive model, the control equations of the corresponding electric field and elastic field and the corresponding electrical and mechanical boundaries need to be introduced;

[0077] (3) Establish a contact geometric model of piezomagnetic particle-piezoelectric matrix composite materials ( Figure 3 As shown). By writing a model script, the distribution method of piezomagnetic particles in the piezoelectric matrix mentioned in the distribution of piezomagnetic particles in the piezoelectric matrix is realized.

[0078] (4) Discretize the geometric model established in (3) ( Figure 4 ). To improve the finite element solution efficiency, the contact area grid is refined. While improving the calculation efficiency, it does not affect the solution accuracy. After grid independence verification, when the grid degrees of freedom reach , further refining the grid has no effect on the solution results.

[0079] (5) Assign material properties. Common piezoelectric materials (PE phase) used to prepare MEE materials include BaTiO3, PZT-x, piezoelectric polymers (PVDF), etc. The piezoelectric effect of piezoelectric materials is determined by the piezoelectric constants e 31 / e 33 / e 15Decision; The piezomagnetic materials (PM phase) commonly used in the preparation of MEE materials include Terfenol-D, CoFe2O4, ZnO, etc. The piezomagnetic effect of the piezomagnetic material is determined by the piezomagnetic constant q 31 / q 33 / q 15 Determined, and the two jointly determine the magnetoelectric coupling variable of the MEE composite material under contact action . Taking typical materials for research, Table 1 and Table 2 respectively give the material parameters of the piezoelectric material BaTiO3 and the piezomagnetic material CoFe2O4. p c ij represents the stiffness coefficient of the piezoelectric material, e ij represents the piezoelectric coupling coefficient, k ij represents the dielectric constant, m c ij represents the elastic coefficient of the piezomagnetic material, q ij represents the piezomagnetic coupling coefficient, μ ij represents the magnetic permeability. Among them, Table 1 is the material parameter of the piezoelectric material BaTiO3, and Table 2 is the material parameter of the piezomagnetic material CoFe2O4;

[0080] Table 1

[0081] Parameter Name Value <![CDATA p c 11 / p c 12 / p c 13 / p c 33 / p c 44 / p c 66 (×10 9 Pa)]]> 166 / 77 / 78 / 162 / 43 / 44.5 <![CDATA[e 31 / e 33 / e 15 (C / m 2 )]]> -4.4 / 18.6 / 11.6 <![CDATA[k 11 =k 22 / k 33 (10 -9 C 2 / (Nm 2 ))]]> 11.2 / 12.6

[0082] Table 2

[0083] Parameter Name Value <![CDATA m c 11 / m c 12 / m c 13 / m c 33 / m c 44 / m c 66 (×10 9 Pa)]]> 286 / 173 / 170.5 / 269.5 / 45.3 / 59.5 <![CDATA[q 31 / q 33 / q 15 (N / (A•m))]]> 580.3 / 699.7 / 550 <![CDATA[μ 11 = μ 22 / μ 33 (10 -6 Ns 2 / C 2 ))]]> 297.5 / 83.5

[0084] (6) Finite element solution and post-processing. Apply loads (longitudinal load Pz, transverse load Px, electrical load g, magnetic load q) to the MEE composite contact model, solve the finite element model, and perform convergence judgment during the solution process. If it converges, perform post-processing, record the calculation results, and calculate the magnetoelectric coefficient; if it does not converge, check the above steps until convergence.

[0085] Constitutive model:

[0086] The Voigt form of the force-magnet constitutive model described in step (1) can be expressed as:

[0087] ;

[0088] Among them, , , , , , represent the piezomagnetic stress, , , represent the magnetic field strength, , , represents magnetic flux, , , , , , represents piezomagnetic strain, represents the elastic coefficient of piezomagnetic material, represents the piezomagnetic coupling coefficient, represents magnetic permeability.

[0089] The Voigt form of the force-electric constitutive model described in step (2) can be expressed as:

[0090] ;

[0091] where , , , , , represent piezoelectric stress, , , represent electric field strength, , , represent electric displacement, , , , , represent piezoelectric strain, represents the elastic coefficient of piezomagnetic material, represents the piezoelectric coupling coefficient, represents conductivity.

[0092] Control equations:

[0093] The control equations of the elastic field, magnetic field, and electric field involved in steps (1) and (2) can be expressed as:

[0094] ;

[0095] In the formula , , , , , represent piezomagnetic stress, , , , , , represent piezoelectric stress, , , represents magnetic flux, , , represents electric field strength, " " is the partial differential symbol.

[0096] In this embodiment, the deformation of the MEE composite material under contact action is still within the elastic range, satisfying the small deformation theory. At the same time, according to the theories of magnetostatics and electrostatics, we have:

[0097] ;

[0098] In the formula , , , , , represent piezomagnetic strain, , , , , represent piezoelectric strain, represents magnetic flux density, , , represent electric field strength, represents the magnetic potential at the grid node, represents the electric potential at the grid node, represents the displacement component at the piezomagnetic phase grid node, represents the displacement component at the piezoelectric phase grid node, " " is the partial differential symbol.

[0099] Boundary conditions:

[0100] Taking the infinitely far away at the bottom of the MEE composite material as the zero magnetic potential end and the grounded end, and at the same time the displacement of the MEE composite material at infinity should be zero, then the magnetic, mechanical, and electrical boundaries involved in steps (1) and (2) can be expressed as:

[0101] ;

[0102] In the formula, represents the displacement component at the piezomagnetic phase grid node, represents the displacement component at the piezoelectric phase grid node, represents the magnetic potential at the grid node, represents the electric potential at the grid node.

[0103] In the contact area, the loading conditions of the MEE composite material:

[0104] ;

[0105] Where represents the corresponding stress components of the matrix (i = m, p), represents the tangential force of the grid nodes in the contact area, the normal force of the grid nodes in the contact area, represents the total tangential load, represents the total normal load, represents the electric displacement component, represents the magnetic flux component, g represents the electric load, and q represents the magnetic load.

[0106] Obtain the influence law of a single parameter pair on:

[0107] The magnetoelectric coupling variables of the MEE composite under contact load have a strong size effect. Considering the microstructure of the MEE material, such as the piezomagnetic particle radius r and the particle volume fraction v f , and combining the actual working conditions during the contact process of the MEE composite material, considering the indenter radius R, the indentation depth as an example (another expression of the longitudinal force load Pz, used to adjust the magnetoelectric coupling variables), respectively change the above parameters to construct a finite element numerical model, and solve it according to the finite element solution process given in step 5.

[0108] Figure 5 , Figure 6 is the finite element solution result, Figure 7 , Figure 8 is the influence of the microstructure of the MEE composite material, the indenter radius R, and the indentation depth on the magnetoelectric coefficient influence.

[0109] Adjust the magnetoelectric coupling variables under force load Formula fitting:

[0110] Take Figure 7 , the influence laws of the 8 parameters r, vf, R, and the indentation depth ω on the magnetoelectric coefficient are presented in the form of an analytical formula. At the microscale, considering the piezomagnetic particle radius r ∈ [1μm, 50μm], the volume fraction vf of piezomagnetic particles and piezoelectric matrix ∈ [0, 1], and the indenter radius R ∈ [0.1mm, 1mm].

[0111] ;

[0112] In this embodiment, a general model for realizing the functional properties of MEE composites through contact action is established. Taking the MEE composite of a piezoelectric matrix containing piezomagnetic particles as an example, through the multi-physics coupling theory and the finite element numerical simulation method, the regulation mechanism of force load on the magnetoelectric coupling variables is systematically revealed.

[0113] It is characterized by considering the microstructures of MEE composites (such as the piezomagnetic particle size r and volume fraction vf) and the macroscopic contact parameters (the indenter radius R, the indentation depth ω, and the regulation parameters of the actual working conditions during the contact process of MEE composites). Combining the constitutive equations of the piezoelectric phase and the piezomagnetic phase with the actual working condition boundaries, the successful regulation of the magnetoelectric coupling variables by the force load is achieved. Prediction of objective laws (which can be obtained by substituting the indentation depth ω under the actual contact working conditions of MEE composites into the expression).

[0114] Application scenarios: Information writing / erasing in large-capacity disk memories. Its mechanical energy consumption is much lower than that of traditional disks, which can effectively extend the service life of disks. This embodiment can be used for the equivalent calculation of the information writing rate of new disk memories made of MEE composites. Application in nanogenerators. By regulating the magnetoelectric coupling variables of MEE composites through contact action, an efficient and flexible conversion scheme is provided for micro-nanogenerators, with the energy conversion rate increased by 10 - 20 percentage points compared to traditional piezoelectric materials. This embodiment can be directly used for the numerical calculation of the conversion of mechanical energy to electrical energy in MEE composite nanogenerators. Micro contact magnetoelectric sensors. Contact sensors can adapt to complex environments. At the same time, due to the small size and light weight of MEE composites, the displacement detection resolution can reach the micron level, which can greatly promote the popularization of portable detection devices. This embodiment can be used as the development of pressure detection and packaging procedures for micro contact magnetoelectric sensors.

[0115] The above is only a preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed in the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A calculation method for the piezoelectric matrix contact magnetoelectric coupling variable containing piezomagnetic particles, characterized in that, Including: Simplify the actual contact situation of the composite material into a contact model of a rigid indenter and a half-space MEE composite material; According to the MEE composite material contact model, establish a force-magnetic coupling constitutive model, and solve the magnetic and mechanical physical quantities during the piezomagnetic phase contact according to the elastic field, magnetic field control equations, and magnetic and mechanical boundaries; According to the MEE composite material contact model, establish a force-electric coupling constitutive model, and solve the electrical and mechanical physical quantities during the piezoelectric phase contact according to the elastic field, electric field control equations, and electrical and mechanical boundaries; Based on the solutions of the magnetic and mechanical physical quantities and the electrical and mechanical physical quantities, establish a contact geometry model of a piezomagnetic particle-piezoelectric matrix composite material considering the microstructure; Discretize the contact geometry model of the piezomagnetic particle-piezoelectric matrix composite material considering the microstructure, and at the same time endow the discretized piezomagnetic particle-piezoelectric matrix composite material geometry model with material properties; Apply a load to the model after endowing it with material properties, complete the solution of the finite element numerical model, perform post-processing, and obtain the magnetoelectric coupling variables.

2. The method according to claim 1, characterized in that, The process of simplifying the actual contact situation of the composite material into a contact model of a rigid indenter and a half-space MEE composite material includes: Taking the contact point of the rigid indenter and the half-space MEE composite material as the coordinate origin, establish a rectangular coordinate system. The rigid indenter contacts the MEE composite material under the action of longitudinal and transverse loads, and construct the contact model of the rigid indenter and the half-space MEE composite material.

3. The method according to claim 1, characterized in that, The process of solving the magnetic and mechanical physical quantities during the piezomagnetic phase contact includes: Construct a force-magnetic coupling constitutive model based on the linear force-magnetic coupling relationship; Substitute the elastic field, magnetic field control equations, and magnetic and mechanical boundary conditions into the force-magnetic coupling constitutive model to complete the solution of the magnetic and mechanical physical quantities during the piezomagnetic phase contact.

4. The method according to claim 1, characterized in that, The process of solving the electrical and mechanical physical quantities during the piezoelectric phase contact includes: Construct a force-electric coupling constitutive model based on the linear force-electric coupling relationship; Substitute the elastic field, magnetic field control equations, and electrical and mechanical boundary conditions into the force-electric coupling constitutive model to complete the solution of the electrical and mechanical physical quantities during the piezoelectric phase contact.

5. The method according to claim 3, characterized in that, The Voigt form of the force-magnetic coupling constitutive model can be expressed as: ； Among them, , , , , , represent piezomagnetic stress, , , represent magnetic field intensity, , , represent magnetic flux, , , , , , represent piezomagnetic strain, represents the elastic coefficient of the piezomagnetic material, represents the piezomagnetic coupling coefficient, represents the magnetic permeability; The expressions of the elastic field, magnetic field control equations, and magnetic and mechanical boundary conditions are: ； where , , , , , represent the piezomagnetic stress, represent the magnetic flux density, represents the magnetic potential at the grid node, represents the displacement component at the grid node, " represents the partial differential symbol.

6. The method according to claim 4, characterized in that, The Voigt form of the force-electric coupling constitutive model can be expressed as: ； Among them, , , , , , represent piezoelectric stress, , , represent electric field strength, , , represent electric displacement, , , , , represent piezoelectric strain, represents the elastic coefficient of the piezomagnetic material, represents the piezoelectric coupling coefficient, represents the conductivity; The expressions of the elastic field, electric field control equations, and electrical and mechanical boundary conditions are: ； where , , , , , represent piezoelectric stress, , , represent electric field strength, represents the electric potential at the grid node, represents the displacement component at the grid node, " represents the partial derivative symbol.

7. The method according to claim 1, characterized in that, The radius of the piezomagnetic particles in the contact geometry model of the piezomagnetic particle-piezoelectric matrix composite material follows a normal distribution, and the ratio with the piezoelectric matrix is expressed as: ； In the formula, represents the volume fraction of piezomagnetic particles, represents the side length of a certain cubic sampling interval, represents the radius of a certain piezomagnetic particle within the sampling interval, represents the number of the piezomagnetic particle.

8. The method according to claim 1, characterized in that, The material properties of the contact geometry model of the piezomagnetic particle-piezoelectric matrix composite material include: the stiffness coefficient, piezoelectric coupling coefficient, and dielectric constant of the piezoelectric material, and the elastic coefficient, piezomagnetic coupling coefficient, and magnetic permeability of the piezomagnetic material.

9. The method according to claim 1, characterized in that, The loads include: longitudinal load, transverse load, electrical load, and magnetic load, and the loads within the contact area are: ； where represents the matrix corresponding stress components (i = m, p), represents the tangential force of the grid nodes within the contact area, the normal force of the grid nodes within the contact area, represents the total tangential load, represents the total normal load, represents the electric displacement component, represents the magnetic flux component, g represents the electric load, and q represents the magnetic load.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the method according to any one of claims 1-9.

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