A method for simulating profile milling of carbon fiber reinforced thermoplastic resin matrix composite

Abstract

The application discloses the field of composite material cutting simulation, and discloses a kind of carbon fiber reinforced thermoplastic resin matrix composite profile milling simulation method, comprising the following steps: establishing thermoplastic composite profile milling three-dimensional finite element simulation model;Define the temperature-dependent anisotropic elastoplasticity constitutive model of thermoplastic composite;Define the anisotropic heat transfer process of thermoplastic composite multi-heat source cutting heat generation;Define the failure criterion and damage evolution criterion of thermoplastic composite;Simulation calculation is carried out, and experimental data is verified.The method of the application first considers the influence of profile milling process characteristics and the special material properties of thermoplastic composite on the composite milling simulation process, accurately predicts the mechanical and thermal behavior in the process of composite profile milling, and greatly improves the precision of thermoplastic profile machining process simulation prediction.The modeling process of the method disclosed by the application is simple, and program code can be easily generated, and the application is helpful to improve the design and manufacturing efficiency of composite components.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of composite material cutting simulation, and particularly relates to a carbon fiber reinforced thermoplastic resin-based composite material profile milling simulation method. BACKGROUND

[0002] Carbon fiber reinforced thermoplastic resin-based composite materials (hereinafter referred to as "thermoplastic composite materials") have been widely used in the fields of aerospace, automobile manufacturing, high-end sports products and the like due to their outstanding characteristics such as excellent specific strength, specific stiffness, impact resistance, corrosion resistance and excellent recyclability. However, in the actual profile milling process of the thermoplastic composite material, due to its unique material properties, including high temperature sensitivity, easy high-temperature phase transition and strong plastic deformation ability, defects such as unstable machining quality, poor surface quality, burrs and delamination are prone to occur in the milling process, which seriously affects the machining quality and actual application of the composite material component. Finite element simulation is an effective method for simulating the material cutting process and machining damage, which is helpful to clarify the material removal mechanism and milling damage formation mechanism in the milling process.

[0003] In recent years, there have been some achievements in the simulation research of thermoplastic composite milling. For example, the research results published in international authoritative journals such as Composite Structures, Journal of Materials Processing Technology, etc. in recent years show that the existing simulation methods are mostly developed for the milling of thermosetting resin-based composites or general metal materials. The simulation model usually ignores the high temperature phase change of thermoplastic composites and the high sensitivity of the material to temperature, resulting in a large deviation between the simulation prediction results and the actual processing effect. For example, in the paper titled "Temperature-dependent cutting physics in orthogonal cutting of carbon fibre reinforced thermoplastic (CFRTP) composite" published by Jia Ge et al. in Composites Part A, Vol. 176, 2024, a thermal-mechanical coupled finite element model of thermoplastic composite is proposed, but the specific geometric and dynamic conditions of profile milling are not fully considered. In addition, although the paper titled "Composite light ropes model-based dynamics force prediction model of high speed dry milling UD-CF / PEEK considering size effect" published by Yang Song et al. in Journal of Manufacturing Processes, Vol. 76, 210-222, 2022, proposes a mechanical model suitable for thermoplastic composite milling, the consideration of the profile milling process characteristics is still insufficient.

[0004] Therefore, there is still an urgent need to develop a high-precision simulation method that can fully consider the profile milling process characteristics and the special material characteristics of thermoplastic composites, so as to effectively guide the actual processing technology, optimize the processing parameters, and improve the processing quality of composite parts. SUMMARY

[0005] The present application is to overcome the defects of the prior art, and to invent a carbon fiber reinforced thermoplastic resin-based composite profile milling simulation method. This method considers the profile milling process characteristics and the characteristics of thermoplastic composites, and can effectively predict the deformation, temperature distribution and material failure of thermoplastic composites during profile milling.

[0006] The technical scheme of the present application is as follows:

[0007] A carbon fiber reinforced thermoplastic resin-based composite profile milling simulation method, the steps are as follows:

[0008] First step: Establishing the three-dimensional finite element simulation model of thermoplastic composite profile milling.

[0009] Using three-dimensional modeling software, a three-dimensional finite element simulation model of thermoplastic composite profile milling is established, which includes the constitutive model of thermoplastic composite, the process of multi-heat source cutting heat generation and anisotropic heat transfer of thermoplastic composite, the failure criterion and damage evolution process of thermoplastic composite, the geometric parameters of the tool, the milling path and the milling parameters, and the boundary conditions are applied; wherein,

[0010] The geometric parameters of the tool include diameter, rake angle and relief angle;

[0011] The milling path includes the machining trajectory and the feed mode;

[0012] The milling parameters include the rotational speed, the feed speed and the cutting depth;

[0013] The boundary conditions include the fixed support, the constraint and the clamping condition;

[0014] Second step: Defining the temperature-dependent anisotropic elastoplastic constitutive model of thermoplastic composite.

[0015] Thermoplastic composite is an anisotropic elastoplastic material, and its constitutive model is closely related to temperature; in the simulation, the temperature-dependent anisotropic elastoplastic constitutive model of thermoplastic composite is defined, in which the plastic behavior is described by a three-dimensional plastic potential function with temperature influence factor; the cutting process includes the deformation and removal process of thermoplastic composite, which is described by state variables for six stress components and six strain components of thermoplastic composite; in the simulation process, after completing the cutting of each increment step, the increments of each stress component and the increments of each strain component in the current increment step are solved, and are superimposed with the stress components and the strain components at the beginning of the current increment step, and then the stress components and the strain components at the end of the current increment step are obtained; in the simulation process, the six stress components and the six strain components of thermoplastic composite are updated once for each increment step of cutting, to ensure that the temperature-dependent anisotropic elastoplastic constitutive model of thermoplastic composite can be accurately expressed in the simulation process.

[0016] Third step: Defining the process of multi-heat source cutting heat generation and anisotropic heat transfer of thermoplastic composite.

[0017] The multi-heat source cutting heat generation of thermoplastic composite has three sources, including anisotropic plastic deformation heat, chip and rake face friction heat, and relief face and machined surface friction heat; the heat of the three heat sources needs to be solved respectively;

[0018] (1) Anisotropic plastic deformation heat: Because the stress-strain relationship of each direction of the thermoplastic composite material is different, when solving the anisotropic plastic deformation heat, the plastic deformation energy of six directions is solved by using the deviatoric stress tensor and the equivalent plastic strain increment, respectively, the total plastic deformation energy is superimposed, and the conversion rate of the total plastic deformation energy to the plastic deformation heat is set, and finally the anisotropic plastic deformation heat is obtained, as shown in the formula

[0019]

[0020] In the formula, S is the deviatoric stress tensor of the unit body at the beginning of the current increment step, S' is the deviatoric stress tensor of the unit body at the end of the current increment step, Δε is the plastic strain increment in the current increment step; S, S' and Δε also have six components, respectively consistent with the direction of the six stress components; S includes six components, respectively S 11 , S 22 , S 33 , S 12 , S 13 , S 23 ; S' includes six components, respectively S' 11 , S' 22 , S' 33 , S' 12 , S' 13 , S' 23 ; Δε includes six components, respectively Δε 11 , Δε 22 , Δε 33 , Δε 12 , Δε 13 , Δε 23 ; Q p is the anisotropic plastic deformation heat, Q pastic is the anisotropic plastic deformation energy, β1 is the proportion of the conversion of the anisotropic plastic deformation energy to the anisotropic plastic deformation heat;

[0021] (2) Friction heat between rake face and chip: When the thermoplastic composite material is cut, continuous long chip is generated, and the chip and the rake face continuously rub to generate friction heat; when solving the friction heat between the rake face and the chip, the friction heat source between the rake face and the chip is a rectangular heat source located on the rake face, the heat flux density on the unit contact area between the rake face and the chip per unit time is calculated according to the contact pressure between the rake face and the chip, and then multiplied by the contact area between the rake face and the chip, to obtain the friction heat between the rake face and the chip per unit time, as shown in the formula

[0022]

[0023] In the formula, q​​γ q is the heat generated per unit time per unit area on the rake face, p N1 p is the average contact pressure between the chip and the rake face, μ1 is the friction coefficient between the chip and the rake face, v ch v is the chip flow velocity, β2 is the proportion of the friction work between the rake face and the chip converted into friction heat, A γ A is the contact area between the chip and the rake face, l f l is the contact length of the rake face and the chip, a w a is the cutting width, Q γ Q is the friction heat per unit time between the rake face and the chip;

[0024] (3) Friction heat between the flank face and the machined surface: the machined surface after springback is continuously rubbed with the flank face, and the friction heat is generated; when the friction heat between the flank face and the machined surface is solved, the friction heat source between the flank face and the machined surface is a moving rectangular heat source located on the flank face; the heat flux density per unit contact area on the flank face per unit time is calculated according to the contact pressure between the flank face and the machined surface, and then multiplied by the contact area between the flank face and the machined surface, so as to obtain the friction heat per unit time between the flank face and the machined surface, as shown in formula

[0025]

[0026] In the formula, q α q is the heat generated per unit time per unit area on the flank face, p N2 p is the average contact pressure between the flank face and the machined surface, μ2 is the friction coefficient between the flank face and the machined surface, v cn v is the relative motion velocity between the flank face and the machined surface, β3 is the proportion of the friction work between the flank face and the machined surface converted into friction heat, A α A is the contact area between the flank face and the machined surface, l c l is the contact length of the flank face and the machined surface, Q α Q is the friction heat per unit time between the flank face and the machined surface;

[0027] Anisotropic heat transfer process: the thermal conductivity coefficient of the thermoplastic composite is also anisotropic, and the anisotropic thermal conductivity coefficient is set when the cutting heat transfer process is solved; in addition, the heat convection heat transfer coefficient between the thermoplastic composite and the tool and the environment is also set;

[0028] Step 4: define the failure criterion and damage evolution criterion of the thermoplastic composite.

[0029] ​According to the actual process characteristics of profile milling, combined with the failure mode of thermoplastic composite, a failure criterion is established, and a corresponding damage evolution criterion is further set to accurately simulate the occurrence and expansion of thermoplastic composite damage.

[0030] Step 5: Perform simulation calculation and verify combined with experimental data.

[0031] Perform finite element simulation calculation, output and analyze the cutting force of thermoplastic composite in the milling process, and compare and analyze the calculation results with the experimental measurement results to verify and calibrate the simulation model.

[0032] The effective effect of the application: the application accurately considers the profile milling process characteristics and the special material properties of thermoplastic composite, can accurately predict the mechanical and thermal behavior in the composite milling process, greatly improves the precision of thermoplastic profile machining process simulation prediction, and helps to improve the design and manufacturing efficiency of composite components. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 is a thermoplastic composite profile milling simulation model in the specific embodiment as a representative example;

[0034] Figure 2 is the calculation precision comparison result of the method of the application and the existing method;

[0035] Figure 3 is a structural flowchart of the application. DETAILED DESCRIPTION

[0036] The specific embodiments of the application will be further described below in combination with the drawings and technical solutions.

[0037] A carbon fiber reinforced thermoplastic resin matrix composite profile milling simulation method not only considers the characteristics of composite profile milling process, but also considers the characteristics of thermoplastic composite multi-heat source cutting heat generation, anisotropic heat conduction and temperature-dependent anisotropic elastic-plastic constitutive model, and can effectively predict the cutting force, temperature distribution and material failure of thermoplastic composite in the profile milling process.

[0038] The specific steps are as follows:

[0039] Step 1: Establish a three-dimensional finite element simulation model of thermoplastic composite profile milling;

[0040] A three-dimensional modeling software is used to establish a three-dimensional finite element simulation model of thermoplastic composite profile milling, which includes a thermoplastic composite constitutive model, a thermoplastic composite multi-heat source cutting heat generation and anisotropic heat conduction process, a thermoplastic composite failure criterion and damage evolution process, tool geometry parameters, milling path and milling parameters, and boundary conditions are applied. Among them,

[0041] The unidirectional thermoplastic composite plate is selected for the research, and the material is CF / PEEK, the carbon fiber model is T700, the PEEK brand is 450G, and the fiber volume fraction is 60%. The four-blade ball milling cutter is selected, and the cutter core thickness is 6mm.

[0042] The tool geometry parameters include tool diameter, tool rake angle and tool relief angle, the tool diameter is 10mm, the tool rake angle is 6°, and the tool relief angle is 12°;

[0043] The milling path includes machining track and feeding mode, the machining track is selected as Z-shaped track, and the feeding mode is down milling;

[0044] The milling parameters include rotating speed, feeding speed and cutting depth, the rotating speed is 3000r / min, the feeding speed is 100mm / min, and the cutting depth is 2mm;

[0045] The boundary conditions include fixed support, constraint and clamping conditions: the upper and lower clamping method is adopted to fix the thermoplastic composite workpiece in the embodiment, the upper and lower surfaces, left and right side surfaces and the non-cutting area part behind are fixed and constrained, and the six-direction freedom degrees of the thermoplastic composite workpiece are limited.

[0046] Second step: define the temperature-dependent anisotropic elastoplastic constitutive model of thermoplastic composite;

[0047] Thermoplastic composite is a typical anisotropic material, and the performance difference between the fiber axial direction and the vertical fiber axial direction is large. Taking CF / PEEK as an example, research shows that the fiber axial direction is linearly elastic, and the vertical fiber axial direction is typically elastoplastic. In order to truly and effectively simulate the stress-strain relationship of thermoplastic composite in the cutting process, a three-dimensional elastoplastic temperature-dependent constitutive model is established. The constitutive model is linearly elastic along the fiber direction and elastoplastic perpendicular to the fiber direction. In addition, a temperature influence factor is added to the constitutive model to reflect the influence of temperature on the stress-strain relationship of thermoplastic composite.

[0048] For orthotropic anisotropic materials, the unit stiffness matrix is:

[0049]

[0050] In the formula,

[0051]

[0052] In the formula, 1 direction is along the fiber direction, which is considered as linearly elastic; 2 direction is perpendicular to the fiber direction, and 3 direction is the thickness direction of the layer, both 2 and 3 directions are considered as elastoplastic. C ij The unit stiffness matrix of the thermoplastic composite is C 11 , C22 , C 33 , C 12 , C 13 , C 23 ; E 11 , E 22 , E 33 , E 12 , E 13 , E 23 are the elastic moduli in six directions respectively; v 11 , v 22 , v 33 , v 12 , v 13 , v 23 are the Poisson's ratios in six directions respectively; G 12 , G 13 , G 23 are the shear moduli in three directions respectively; Δ is an intermediate variable.

[0053] The composite material is orthotropic as a whole. Then the three-dimensional plastic potential function can be expressed as:

[0054]

[0055] where a66 is a coefficient representing anisotropic plasticity, and a66 = 2. σ 11 , σ 22 , σ 33 , σ 12 , σ 13 , σ 23 are stress components respectively. Then the three-dimensional equivalent stress can be expressed as:

[0056]

[0057] The plastic strain increment is:

[0058]

[0059] where dλ is a proportional coefficient, and its expression is:

[0060]

[0061]

[0062] The plastic strain increment is:

[0063]

[0064] wherein, is the engineering plastic shear strain.

[0065] The relationship between the equivalent plastic strain and the equivalent stress is:

[0066]

[0067] wherein, A is a parameter related to temperature, and its expression is:

[0068]

[0069] wherein, T is temperature, in ℃.

[0070] Step 3: define the multi-heat source cutting heat generation and anisotropic heat transfer process of the thermoplastic composite material;

[0071] The multi-heat source cutting heat generation of the thermoplastic composite material has three sources, including anisotropic plastic deformation heat, chip and rake face friction heat, and relief face and machined surface friction heat; the heat of the three heat sources needs to be solved respectively;

[0072] (1) Anisotropic plastic deformation heat: since the stress-strain relationship of the thermoplastic composite material in each direction is different, when solving the anisotropic plastic deformation heat, the deviatoric stress tensor and the equivalent plastic strain increment are used to solve the plastic deformation energy in six directions respectively, the total plastic deformation energy is obtained by superposition, and the conversion rate of the total plastic deformation energy to the plastic deformation heat is set, and finally the anisotropic plastic deformation heat is obtained, as shown in the following formula:

[0073]

[0074] (2) Rake face and chip friction heat: continuous long chips are generated during the cutting of the thermoplastic composite material, and the continuous friction between the chips and the rake face generates friction heat; when solving the rake face and chip friction heat, the friction heat source between the rake face and the chip is a rectangular heat source located on the rake face, the heat flux density on the unit contact area between the rake face and the chip per unit time is calculated according to the contact pressure between the rake face and the chip, and then the contact area between the rake face and the chip is multiplied, so as to obtain the friction heat between the rake face and the chip per unit time, as shown in the following formula:

[0075]

[0076] (3) Friction heat between the flank face and the machined surface: the machined surface after springback is prone to continuous friction with the flank face to generate friction heat; in solving the friction heat between the flank face and the machined surface, the friction heat source between the flank face and the machined surface is a moving rectangular heat source on the flank face, the heat flux density on the unit contact area between the flank face and the machined surface per unit time is calculated according to the contact pressure between the flank face and the machined surface, and then multiplied by the contact area between the flank face and the machined surface, so as to obtain the friction heat between the flank face and the machined surface per unit time, as shown in the following formula:

[0077]

[0078] (4) Anisotropic heat transfer process: the thermal conductivity of the thermoplastic composite is also anisotropic, and the anisotropic thermal conductivity is set when solving the cutting heat transfer process; in addition, the heat convection heat transfer coefficient between the thermoplastic composite and the tool and the environment also needs to be set.

[0079] When the thermoplastic composite is cut, the materials at different positions from the tool tip have different deformation behaviors due to different cutting forces, and the cutting heat production is naturally different, which is difficult to directly calculate. The present embodiment adopts a "single-point solution-whole superposition" heat transfer calculation method for the problem that the heat production at different positions in cutting is different and cannot be simply calculated. That is, the temperature field under the action of each point heat source can be solved first, and then the temperature fields of all point heat sources are superposed to obtain the temperature field in the whole cutting process. The Jaeger heat source model is often used to solve this problem, and the heat transfer formula is as follows:

[0080]

[0081] The initial temperature condition is as follows:

[0082]

[0083] The heat flow boundary condition is as follows:

[0084]

[0085] In the formula, k1, k2 and k3 are the thermal conductivities of the thermoplastic composite along the x-axis, y-axis and z-axis directions respectively; g(x, y, z, t) is a heat source term in the model, which represents the three-dimensional coordinates of the heat source and its change with time; p and c represent the density and specific heat capacity of the thermoplastic composite respectively, T0 is the initial temperature of the model, q instant represents the heat flow size of the point heat source at this moment; is the moving speed of the heat source;

[0086] At the initial time t=0, suppose that a point heat source appears at (x', y', z') and disappears instantaneously, then the heat transfer process of the heat source in the model can be calculated by the solving method of the transient point heat source anisotropic temperature field in the Jaeger model, as follows:

[0087]

[0088] The temperature field of the entire workpiece can be expressed as follows:

[0089]

[0090] In the formula, a, b and c are three-dimensional dimensions of the workpiece, respectively.

[0091] Fourth step: defining the failure criterion and damage evolution criterion of the thermoplastic composite material;

[0092] In this embodiment, the three-dimensional Hashin criterion is used as the failure initiation criterion of the thermoplastic composite material, as shown in the following formula:

[0093]

[0094] The linear damage evolution criterion is used to describe the damage evolution process, as shown in the following formula:

[0095]

[0096] Fifth step: simulation calculation and verification combined with experimental data;

[0097] Taking the commonly used commercial analysis software ABAQUS (version 6.16) as an example, according to the derivation of the above first to fourth steps, the VUMAT user subroutine for ABAQUS / EXPLICT is written and input into the simulation software. The three-dimensional finite element model of the thermoplastic composite material surface milling is established as shown in the following formula: Figure 1 The method proposed in the application is used for calculation, and the average value of the main cutting force is used as an index to compare the simulation calculation accuracy. The model setting and material properties are shown in Tables 1 and 2, respectively, and other settings are described in detail in the literature Elliptic vibration-assisted cutting of fibre-reinforced polymer composites: Understanding the material removal mechanisms. The accuracy comparison result is shown in the following formula: Figure 2

[0098] Table 1 represents the simulation model setting of a representative example ​

[0099]

[0100] Table 2 Material properties of representative simulation models

[0101]

[0102] Depend on Figure 2 It is evident that the simulation method for milling thermoplastic composite profiles proposed in this invention can significantly reduce the calculation error of cutting forces in thermoplastic composites. Compared with existing methods, the calculation error can be reduced by more than 24%.

Claims

1. A method of simulating profile milling of a carbon fiber reinforced thermoplastic resin matrix composite material, characterized by, The steps are as follows: Step 1: Establish a three-dimensional finite element simulation model for thermoplastic composite profile milling; Use three-dimensional modeling software to establish a three-dimensional finite element simulation model for thermoplastic composite profile milling, which includes the constitutive model of thermoplastic composite, the process of anisotropic heat transfer of thermoplastic composite multi-source cutting heat generation, the failure criterion and damage evolution process of thermoplastic composite, the geometric parameters of the tool, the milling path, and the milling parameters, and apply boundary conditions; among them, The tool geometry parameters include diameter, rake angle and relief angle; The milling path includes the machining trajectory and the feed mode; The milling parameters include speed, feed speed and cutting depth; The boundary conditions include fixed support, constraint and clamping conditions; Step 2: Define the temperature-dependent anisotropic elastoplastic constitutive model of thermoplastic composite; Thermoplastic composite is an anisotropic elastoplastic material, and its constitutive model is closely related to temperature; when simulating, define the temperature-dependent anisotropic elastoplastic constitutive model of thermoplastic composite, in which the plastic behavior is described by a three-dimensional plastic potential function with temperature influence factor; the cutting process includes the deformation and removal process of thermoplastic composite, which is described by state variables for six stress components and six strain components of thermoplastic composite; during the simulation process, after completing the cutting of each increment step, the increments of each stress component and the increments of each strain component in the current increment step are solved, and are superimposed with the stress components and strain components at the beginning of the current increment step, to obtain the stress components and strain components at the end of the current increment step; during the simulation process, after completing the cutting of each increment step, the six stress components and six strain components of thermoplastic composite are updated once; Step 3: Define the process of anisotropic heat transfer of thermoplastic composite multi-source cutting heat generation; There are three sources of thermoplastic composite multi-source cutting heat generation, including anisotropic plastic deformation heat, chip and rake face friction heat, and relief face and machined surface friction heat; the heat solution of the three heat sources is as follows: (1) Anisotropic plastic deformation heat: Since the stress-strain relationship in each direction of thermoplastic composite is different, when solving the anisotropic plastic deformation heat, the plastic deformation energy in six directions is solved by using the deviatoric stress tensor and the equivalent plastic strain increment, respectively, the total plastic deformation energy is obtained by superposition, and the conversion rate of the total plastic deformation energy to the plastic deformation heat is set, and finally the anisotropic plastic deformation heat is obtained; (2) Rake face and chip friction heat: continuous long chips are generated during the cutting of thermoplastic composite, and the continuous friction between the chip and the rake face generates friction heat; when solving the rake face and chip friction heat, the friction heat source between the rake face and the chip is a rectangular heat source located on the rake face, the heat flux density on the unit contact area between the rake face and the chip per unit time is calculated according to the contact pressure between the rake face and the chip, and then the contact area between the rake face and the chip is multiplied, to obtain the rake face and chip friction heat per unit time; (3) Friction heat between the flank face and the machined surface: the machined surface after springback is continuously rubbed with the flank face, which generates friction heat; in solving the friction heat between the flank face and the machined surface, the friction heat source between the flank face and the machined surface is a moving rectangular heat source on the flank face; according to the contact pressure between the flank face and the machined surface, the heat flux density on the unit contact area between the flank face and the machined surface per unit time is calculated, and then multiplied by the contact area between the flank face and the machined surface, so as to obtain the friction heat between the flank face and the machined surface per unit time; Anisotropic heat transfer process: the thermal conductivity coefficient of the thermoplastic composite is also anisotropic, and in solving the cutting heat transfer process, the anisotropic thermal conductivity coefficient is set; in addition, the heat convection heat transfer coefficient between the thermoplastic composite and the tool and the environment also needs to be set; Step 4: define the failure criterion and damage evolution criterion of the thermoplastic composite; According to the actual process characteristics of profile milling, combined with the failure mode of the thermoplastic composite, the failure criterion is established, and the corresponding damage evolution criterion is further set to accurately simulate the occurrence and expansion of the damage of the thermoplastic composite; Step 5: perform simulation calculation and verify it by combining experimental data; Perform finite element simulation calculation, output and analyze the cutting force of the thermoplastic composite in the milling process, compare and analyze the calculation results with the experimental measurement results, verify and calibrate the three-dimensional finite element simulation model of the thermoplastic composite profile milling.

2. The carbon fiber reinforced thermoplastic resin-based composite profile milling simulation method according to claim 1, characterized by, The solution process of the anisotropic plastic deformation heat is shown in equation (1): (1); wherein S is the deviatoric stress tensor of the element at the beginning of the current increment step, S is the deviatoric stress tensor of the element at the end of the current increment step, Δ ε is the plastic strain increment in the current increment step; S , S , ε also have six components, respectively, in the directions of the six stress components; S include six components, respectively, S 11 , S 22 , S 33 , S 12 , S 13 , S 23 ; S include six components, respectively, S 11 , S 22 , S 33 , S 12 , S 13 , S 23 ; Δ ε include six components, respectively, Δ ε 11 , Δ ε 22 , Δ ε 33 , Δ ε 12 , Δ ε 13 , Δ ε 23 ; Q p is the anisotropic plastic deformation heat, Q pastic is the anisotropic plastic deformation energy, β 1 is the proportion of the anisotropic plastic deformation energy converted into the anisotropic plastic deformation heat.​​​​​​ 3. The method of claim 1, wherein, The solution process of the friction heat between the rake face and the chip per unit time is shown as equation (2). (2); wherein, q γ is the heat generated per unit time per unit area on the rake face, p N1 is the average contact pressure between the chip and the rake face, μ 1 is the friction coefficient between the chip and the rake face, v ch is the chip flow velocity, β 2 is the proportion of the friction work between the rake face and the chip that is converted into friction heat, A γ is the contact area between the chip and the rake face, l f is the contact length of the rake face with the chip, a w is the cutting width, Q γ is the friction heat per unit time between the rake face and the chip.

4. The method of claim 1, wherein, The solving process of the friction heat between the relief surface and the machined surface per unit time is shown as equation (3): ; wherein q α Q is the heat generated per unit time per unit area on the flank face, p N2 P is the average contact pressure between the flank face and the machined surface, μ 2 is the coefficient of friction between the flank face and the machined surface, v cn V is the relative velocity between the flank face and the machined surface, β 3 is the proportion of the frictional work between the flank face and the machined surface that is converted into frictional heat, A α A is the contact area between the flank face and the machined surface, l c L is the contact length between the flank face and the machined surface, Q α Q is the heat generated per unit time by friction between the flank face and the machined surface, a w B is the cutting width.

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