A composite material impact calculation method considering temperature effects

Abstract

The present invention discloses a composite material impact calculation method considering the influence of temperature, comprising the following steps: establishing a composite material stress-strain relationship affected by temperature, correcting the elastic modulus and strength of the composite material affected by temperature and strain rate, determining failure units according to the 3D-Hashin failure criterion, and establishing a stiffness reduction degradation model; conducting high-speed impact tests on composite laminates at different temperatures, collecting bullet velocities and laminate damage as test sample data; and calculating the 50% penetration velocity V by taking the velocities of six measuring points with opposite results of the three highest blocking velocities and the three lowest penetration velocities, which are equal in number. 50 Comparing penetration velocities at different temperatures revealed that the impact resistance of composite laminates decreases with increasing ambient temperature. Simulations were performed using the finite element method (Abaqus) and compared with experimental results. This approach incorporated temperature effects into the high-speed impact of composite materials, simulating the service environment of aircraft engine fan cases and improving their containment.

Description

Technical Field

[0001] The present invention belongs to the technical field of composite material impact technology, and in particular relates to a composite material impact calculation method considering temperature influence. Background Art

[0002] Replacing metal materials with resin-based composites in aircraft engines to achieve lightweighting is an effective way to optimize aircraft engine performance and improve thrust-to-weight ratio. It is also a key trend in the development of future aircraft engine material systems. The current state of research on composite impact testing and finite element numerical simulation shows that most experimental studies are conducted at room temperature. Experimental studies on composite impact in high-temperature environments are relatively rare. Furthermore, fiber-reinforced composites exhibit diverse dynamic mechanical behaviors due to the complexity of their components, preparation processes, and inherent structures, making them difficult to describe using a unified constitutive theory. Due to the complexity of the components, preparation processes, and inherent structures of polyimide fiber-reinforced composites, and considering the temperature environment of aircraft engine fan cases during service and the medium / high strain rate effects during high-speed impact, there is currently no suitable dynamic constitutive model that considers temperature effects for the current problem. Summary of the Invention

[0003] The purpose of the present invention is to overcome the technical defects of the prior art and solve the above-mentioned technical problems. The present invention conducts impact research on composite materials at the service temperature of aircraft engine fan cases to determine the impact resistance of composite materials at service temperature, thereby improving the containment of fan cases and providing a composite material impact calculation method that takes temperature effects into account.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a composite material impact calculation method considering temperature influence, comprising:

[0005] Step 1: Establish a dynamic constitutive model of polyimide fiber reinforced resin matrix composites considering the influence of temperature;

[0006] Step 2: Conduct high-speed impact tests on the composite laminate at different temperatures, and collect bullet velocity and composite laminate damage as test sample data;

[0007] Step 3: Take the three highest blocking velocities and the three lowest penetration velocities from the test sample data in step 2 to calculate V 50 The experimental value of

[0008] Step 4: Establish a finite element model of composite laminates under high-speed bullet impact in a high-temperature environment in the Abaqus program;

[0009] Step 5: Use the Abaqus program to simulate the high-speed impact test in step 2 and obtain V 50The simulation value of .

[0010] Furthermore, the step 1 specifically includes:

[0011] The stress-strain relationship of composite materials affected by temperature is established, and the elastic modulus and strength of composite materials affected by temperature and strain rate are corrected.

[0012] Furthermore, in step 3, V is calculated 50 The formula for the experimental value of is:

[0013]

[0014] in, is the arithmetic mean of the bullet velocity at the measuring point; v i is the velocity of the bullet that effectively hits the measuring point for the i-th round; x is the flight distance from the measuring point to the target; c x is the flight resistance coefficient of the projectile; ρ is the local air density; m f is the mass of the projectile; s is the frontal area of ​​the projectile.

[0015] Furthermore, the specific steps of step 4 include:

[0016] Step 41: Establish a dynamic constitutive model of polyimide fiber reinforced resin matrix composite material considering the temperature effect through VUMAT subroutine definition;

[0017] Step 42: Use the three-dimensional Hashin failure criterion as the failure initiation criterion, introduce damage variables based on the progressive damage accumulation theory and continuum damage mechanics to establish a stiffness reduction degradation model.

[0018] Furthermore, the specific steps of step 41 include:

[0019] Step 411: The influence of temperature on the performance of the composite laminate is considered in the display dynamic iteration step through the vumat subroutine, and the relationship between temperature and the elastic modulus of the composite laminate is:

[0020]

[0021] The relationship between temperature and the strength parameters of composite laminates is:

[0022]

[0023] Among them, E1, E2, E3, G 12 , G 13 and G 23 is the initial elastic modulus parameter of the composite laminate, the superscript T represents the temperature effect, T g is the dry glass transition temperature of the resin in the composite material, T is the current temperature, T0 is the room temperature, Xt 、X c 、Y t 、Y c 、S 12 、S 13 and S 23 is the strength parameter of the composite material;

[0024] Step 412: The influence of strain rate on the performance of the composite laminate is considered in the display dynamic iteration step through the vumat subroutine, and the dynamic enhancement factor of the strength of the composite laminate in different directions is:

[0025]

[0026] The relationship between the strain rate in different directions and the strength parameters of the composite laminate is:

[0027]

[0028] The dynamic enhancement factor of the elastic modulus of composite laminates in different directions is:

[0029]

[0030] The relationship between the strain rate in different directions and the elastic modulus of the composite laminate is:

[0031]

[0032] Among them, E and G are the initial elastic modulus parameters of the composite laminate, E rate and G rate are the elastic modulus parameters of the composite laminate after considering the strain rate effect, 1, 2, and 3 are E and E rate The subscripts 12, 23, and 31 are G and G rate The subscript of C rate is the strain rate effect parameter of the composite laminate, X T 、X C 、Y T 、Y C , Z T and Z C is the strength parameter of the composite laminate after considering the strain rate effect, is the strain rate, is the initial strain rate.

[0033] Furthermore, the three-dimensional Hashin failure criterion in step 42 specifically includes:

[0034] Fiber tensile failure mode:

[0035]

[0036] Fiber compression failure mode:

[0037]

[0038] Basic tensile failure modes:

[0039]

[0040] Basic compression failure modes:

[0041]

[0042] Among them, σ ij Represents the components of the stress tensor in the material coordinate system, X represents the material strength in the fiber direction, Y represents the material strength in the direction perpendicular to the fiber, subscripts T and C represent tensile load and compressive load respectively, S ij (i, j = 1, 2, 3; i ≠ j) represents the shear strength of the material.

[0043] Furthermore, the step 5 specifically includes:

[0044] Step 51: The abaqus main program calls the user subroutine VUMAT and passes the user input material parameters to the subroutine;

[0045] Step 52: Correcting the material parameters of the composite laminate at the current temperature;

[0046] Step 53: Calculate the strain rate of the current composite laminate, calculate and update the dynamic enhancement factors of the strength and elastic modulus of the composite laminate in each direction, and correct the material parameters of the composite laminate again;

[0047] Step 54: Based on the defined dynamic constitutive model of the fiber reinforced resin matrix composite material considering the temperature effect, the stress and displacement of the elements divided on the composite laminate are updated and calculated;

[0048] Step 55: Determine whether the elements divided on the composite laminate have failed according to the three-dimensional Hashin failure criterion. If failure has occurred, obtain the failed element and determine the failure mode. If fiber tensile failure has occurred, delete the failed element. Otherwise, degrade the material properties according to the stiffness degradation model.

[0049] Step 56: Update and store state variables;

[0050] Step 57: End the calculation and return to the main program to get V 50 The simulation value of .

[0051] Furthermore, the step 5 further comprises: comparing the damage analysis of the composite laminate obtained by simulation with the actual damage diagram of the composite laminate obtained by the high-speed impact test in step 2, and comparing V 50 The simulation value of V 50 The experimental values ​​were compared.

[0052] Beneficial effects:

[0053] 1. The existing room-temperature high-speed ballistic impact device was upgraded, a high-temperature environment simulation device was added, and the composite laminate specimen fixture was improved. Compared with the room-temperature experimental environment of traditional tests, the experimental environment is closer to the service temperature of the fan case.

[0054] 2. Calculate the ballistic limit velocity V of composite laminates at different temperatures 50 and ballistic energy absorption EA, the calculation results show that the high-speed impact resistance of composite laminates decreases with the increase of ambient temperature.

[0055] 3. In the simulation, the three-dimensional Hashin failure criterion is used as the failure initiation criterion, and the layer reduction degradation model is used to consider the strain rate and temperature effects to determine the constitutive equation and material parameters of the composite material. A dynamic constitutive model of fiber-reinforced resin-based composite materials considering the influence of temperature is established. A finite element model of composite laminates subjected to high-speed bullet impact in a high-temperature environment is established, and the constitutive model established is defined using the VUMAT subroutine to analyze and calculate the V of the composite laminates at different temperatures. 50 The finite element simulation values ​​are compared with the test results respectively. At the same time, the impact failure modes of the composite material laminates at different temperatures are analyzed and calculated and compared with the composite material laminates after impact, so as to determine the impact resistance of the composite material at the service temperature and thus improve the inclusiveness of the fan case. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 It is an overall flow chart of the present invention.

[0057] Figure 2 Schematic diagram of a high-speed ballistic impact device used for high-speed impact testing of the present invention.

[0058] Figure 3 Schematic diagram of a high-temperature environment simulation device used for high-speed impact testing of the present invention.

[0059] Figure 4 This is a schematic diagram of the high-temperature environment simulation device used for high-speed impact testing of the present invention during operation.

[0060] Figure 5 A photo of the bullet, sabot, and composite laminate used in the high-speed impact test of the present invention.

[0061] Figure 6 Schematic diagram of the impact resistance of the composite laminate under different ambient temperatures of the present invention.

[0062] Figure 7 This is a real picture of the damage analysis after the high-speed impact test of the present invention at a bullet speed of 273m / s.

[0063] Figure 8 This is a real picture of the damage analysis after the high-speed impact test of the present invention at a bullet speed of 337m / s.

[0064] Figure 9 The impact simulation model of the polyimide fiber reinforced resin matrix composite material established by the present invention is shown in FIG.

[0065] Figure 10 This is a flowchart of step 5 of the present invention.

[0066] Figure 11 Schematic diagram of the damage accumulation history corresponding to the four microscopic failure modes in the simulation of the present invention.

[0067] Figure 12 This is a comparison diagram of the numerical simulation damage in the simulation of the present invention and the actual damage in the high-speed impact test. DETAILED DESCRIPTION

[0068] The present invention will be further explained below with reference to the accompanying drawings.

[0069] like Figure 1 As shown, the present invention provides a composite material impact calculation method considering the temperature effect, comprising:

[0070] Step 1: Establish a dynamic constitutive model of polyimide fiber reinforced resin matrix composites considering the influence of temperature.

[0071] Step 2: Conduct high-speed impact tests on the composite laminate at different temperatures, and collect bullet velocity and composite laminate damage as test sample data.

[0072] Step 3: Take the three highest blocking velocities and the three lowest penetration velocities from the test sample data in step 2 to calculate V 50 The experimental value of .

[0073] Step 4: Establish a finite element model of composite laminates impacted by bullets at high speed under high temperature environment in the Abaqus program.

[0074] Step 5: Use the Abaqus program to simulate the high-speed impact test in step 2 and obtain V 50 The simulation value of .

[0075] The following are specific embodiments of the present invention. The materials in all embodiments are polyimide fiber reinforced resin-based composite materials, and the composite laminates are polyimide fiber reinforced resin-based composite laminates.

[0076] In step 1, the material parameters under different temperature environments are measured, and the effects of ambient temperature and high strain rate on material properties are considered, so as to establish the stress-strain relationship of the composite material affected by temperature, and correct the elastic modulus and strength of the composite material affected by temperature and strain rate.

[0077] In step 2, if Figure 2-4 As shown, impact tests were conducted under different temperature environments. The existing high-speed ballistic impact test equipment was upgraded to include a high-temperature environment simulator. The internal temperature of the high-temperature environment simulator can reach a maximum of 800°C and be stably maintained at the set temperature. The specimen was secured to the test fixture. A high-temperature thermometer sensor was inserted from the junction of the high-temperature chamber and the barrel into the composite laminate to measure the specimen temperature. The specimen was then heated to the test temperature and held at that temperature for 10 minutes before the impact test was conducted. The specimen was the composite laminate.

[0078] like Figure 5 As shown, the composite laminate used in the impact test is a polyimide fiber-reinforced bismaleimide resin-based composite laminate, grade S35 / EC240A. The composite laminate consists of thirty layers, with dimensions of 150 × 100 × 3.7 mm. The bullet has a radius of 4.5 mm and a height of 5 mm. The sabot is made of nylon.

[0079] In step 3, the specimens were divided into three equal groups and tested at 25°C, 160°C, and 200°C. High-temperature impact testing of composite materials was conducted according to the GA950-2019 standard. During the impact test, if the first shot completely penetrated, the pressure of the second shot was reduced by approximately 30 m / s from the first shot, with a single shot considered blocked. If the first two shots both resulted in penetration, the third shot further reduced the pressure by approximately 30 m / s. If the first two shots resulted in opposite results, the third shot's pressure was the average of the first two.

[0080] The test results under three groups of temperatures are shown in the following three tables:

[0081] Table 1 Test results at 25℃

[0082]

[0083] Table 2 160℃ test results

[0084]

[0085] Table 3 200℃ test results

[0086]

[0087] Then count and organize the experimental results.

[0088] The damage morphology of the composite laminate after high-speed bullet impact was analyzed by visual inspection, and it was found that the damage degree of the polyimide fiber reinforced bismaleimide resin-based composite laminate increased with the increase of bullet impact speed.

[0089] Finally, the arithmetic mean of the effective data obtained from the test is calculated and the V of the sample is corrected and calculated. 50 The value is calculated as follows:

[0090]

[0091] Where V is the arithmetic mean of the bullet velocity at the measuring point; v i is the velocity of the bullet that effectively hits the measuring point for the i-th round; x is the flight distance from the measuring point to the target; c x is the flight resistance coefficient of the projectile; ρ is the local air density; m f is the mass of the projectile; s is the frontal area of ​​the projectile.

[0092] And according to sample V 50 The ballistic energy absorption E can be calculated A , as shown below:

[0093]

[0094] According to the above impact test process, the impact test of polyimide fiber reinforced bismuth resin matrix composite material at different temperatures was carried out. According to the ballistic limit velocity V of the fiber reinforced resin matrix composite laminate 50 and ballistic energy absorption E A The high-speed impact resistance of polyimide fiber reinforced bismaleimide resin matrix composites at different ambient temperatures was obtained by using the formula. The results are shown in Table 4. Figure 6 shown.

[0095] Table 4 High-speed impact resistance of polyimide fiber reinforced bismaleimide resin-based composite laminates at different temperatures

[0096]

[0097] Comparing the test results of this paper with those in existing literature, we found that, given the same geometric dimensions and molding process for the composite laminates, the relative errors between the high-speed impact test results at different temperatures and the references were within 5%. Therefore, the test results of this paper are valid and reliable.

[0098] The preparation process of the composite material laminate in this embodiment is as follows:

[0099] EC240A bismaleimide resin was preheated in an oven at 95-100°C for about 30 minutes, and an EC240A resin film of appropriate surface density was scraped on a film machine. The scraping temperature was controlled to (98±3)°C, and then the film and S35 polyimide fiber were compounded on a prepreg machine by a hot melt method to prepare a prepreg with a theoretical single-layer thickness of 0.125 mm after curing. The compounding temperature was 100-105°C.

[0100] The preform is stacked in the desired layup pattern, and then cured in an autoclave to produce a composite laminate. The curing process is as follows: vacuum is drawn at room temperature, with the vacuum level (gas pressure inside the vacuum bag minus atmospheric pressure) not exceeding -0.095 MPa. The pressure is then increased to (0.6±0.02) MPa at room temperature, raised to (180±5)°C, and held constant for 2 hours; then raised to (208±3)°C, and held constant for 6 hours; then raised to (250±3)°C, and held constant for 4 hours (at a rate of 1-1.5°C / min). The pressure is then released from the autoclave at a rate of no more than 2°C / min, to below 60°C.

[0101] The composite laminate was processed into a length of about 150mm and a width of about 100mm using wire cutting technology. The specimen was laid out in layers of [60 / 0 / -60] 5s .

[0102] like Figure 7-8 As shown, they are damage analysis diagrams after impact at bullet speeds of 273m / s and 337m / s respectively. The damage morphology of the composite laminate after high-speed bullet impact was analyzed by visual inspection. Generally speaking, the degree of damage to the polyimide fiber reinforced bismaleimide resin-based composite laminate increases with the increase of bullet impact speed. The impact failure morphology of the polyimide fiber reinforced bismaleimide resin-based composite laminate is mainly divided into pits, bulges, matrix cracks, fiber breakage, fiber compression, delamination, fiber penetrating tearing and other forms. For impacts of different speeds, the area of ​​damage to the composite laminate is different, but has a similar shape.

[0103] In step 4, before simulating the high-speed impact test in step 2, a finite element model of a composite laminate subjected to high-speed bullet impact in a high-temperature environment is first established. The composite laminate is discretized using an 8-node reduced integration element C3D8R, with a total of 450,000 elements. The critical time step is then determined based on the natural frequency of the system, as shown in the following example: Figure 9 shown.

[0104] The specific steps for establishing a finite element model of composite laminates subjected to high-speed bullet impact in a high-temperature environment include:

[0105] Step 41: Define the VUMAT subroutine to establish a dynamic constitutive model of polyimide fiber reinforced resin matrix composite material considering the temperature effect.

[0106] Step 42: Use the three-dimensional Hashin failure criterion as the failure initiation criterion, introduce damage variables based on the progressive damage accumulation theory and continuum damage mechanics to establish a stiffness reduction degradation model.

[0107] The specific steps of establishing a dynamic constitutive model of polyimide fiber reinforced resin matrix composites considering temperature influence through VUMAT subroutine definition include:

[0108] Step 411: The influence of temperature on the performance of the composite laminate is considered in the display dynamic iteration step through the vumat subroutine, and the relationship between temperature and the elastic modulus of the composite laminate is:

[0109]

[0110] The relationship between temperature and the strength parameters of composite laminates is:

[0111]

[0112] Among them, E1, E2, E3, G 12 , G 13 and G 23 is the initial elastic modulus parameter of the composite laminate, the superscript T represents the temperature effect, T g is the dry glass transition temperature of the resin in the composite material, T is the current temperature, T0 is the room temperature, X t 、X c 、Y t 、Y c 、S 12 、S 13 and S 23 is the strength parameter of the composite material.

[0113] Step 412: The influence of strain rate on the performance of the composite laminate is considered in the display dynamic iteration step through the vumat subroutine, and the dynamic enhancement factor of the strength of the composite laminate in different directions is:

[0114]

[0115] The relationship between the strain rate in different directions and the strength parameters of the composite laminate is:

[0116]

[0117] The dynamic enhancement factor of the elastic modulus of composite laminates in different directions is:

[0118]

[0119] The relationship between the strain rate in different directions and the elastic modulus of the composite laminate is:

[0120]

[0121] Among them, E and G are the initial elastic modulus parameters of the composite laminate, E rate and G rate are the elastic modulus parameters of the composite laminate after considering the strain rate effect, 1, 2, and 3 are E and E rate The subscripts 12, 23, and 31 are G and G rate The subscript of C rate is the strain rate effect parameter of the composite laminate, X T 、X C 、Y T 、Y C , Z T and Z C is the strength parameter of the composite laminate after considering the strain rate effect, is the strain rate, is the initial strain rate.

[0122] The three-dimensional Hashin failure criteria specifically include:

[0123] Fiber tensile failure mode:

[0124]

[0125] Fiber compression failure mode:

[0126]

[0127] Basic tensile failure modes:

[0128]

[0129] Basic compression failure modes:

[0130]

[0131] Among them, σ ij Represents the components of the stress tensor in the material coordinate system, X represents the material strength in the fiber direction, Y represents the material strength in the direction perpendicular to the fiber, S ij (i, j = 1, 2, 3; i ≠ j) represents the shear strength of the material, and the subscripts T and C represent the tensile load and compressive load, respectively.

[0132] like Figure 10 As shown, in step 5, the specific simulation steps include:

[0133] Step 51: The abaqus main program calls the user subroutine VUMAT and passes the user input material parameters to the subroutine;

[0134] Step 52: Correcting the material parameters of the composite laminate at the current temperature;

[0135] Step 53: Calculate the strain rate of the current composite laminate, calculate and update the dynamic enhancement factors of the strength and elastic modulus of the composite laminate in each direction, and correct the material parameters of the composite laminate again;

[0136] Step 54: Based on the defined dynamic constitutive model of the fiber reinforced resin matrix composite material considering the temperature effect, the stress and displacement of the elements divided on the composite laminate are updated and calculated;

[0137] Step 55: Determine whether the elements divided on the composite laminate fail according to the three-dimensional Hashin failure criterion. If failure occurs, obtain the failed element and determine the failure mode. If fiber tensile failure occurs, delete the failed element. Otherwise, degrade the material properties according to the stiffness degradation model.

[0138] Step 56: Update and store state variables;

[0139] Step 57: End the calculation and return to the main program to get V 50 The simulation value of .

[0140] In this embodiment, taking the front view of a composite laminate after impact at an ambient temperature of 160°C and an impact velocity of 321 m / s as an example, the damage accumulation history corresponding to the four micro failure modes is obtained, such as Figure 11 The material properties in step 55 refer to the strength and elastic modulus of the composite laminate in each direction.

[0141] After the simulation is completed, the simulation results are used to analyze the damage of the composite laminate and compared with the actual damage diagram, such as Figure 12 As shown. Figure 12 The numerical simulation damage is consistent with the actual test damage.

[0142] At the same time, V 50 The simulation results were compared with the experimental results. The results show that the relative errors between the simulation values ​​and the experimental values ​​of the composite laminates at different temperatures are within 5%, and the numerical simulation results are consistent with the experimental results, as shown in Table 5.

[0143] Table 5 Comparison between ballistic limit velocity simulation and test values

[0144]

[0145] The present invention establishes a temperature-affected stress-strain relationship for composite materials, corrects the elastic modulus and strength of composite materials affected by temperature and strain rate, determines failure units according to the 3D-Hashin failure criterion, and establishes a stiffness reduction degradation model. High-speed impact tests are conducted on composite laminates at different temperatures, and bullet velocities and laminate damage are collected as test sample data. The bullet velocities of six measuring points with opposite results (three with the highest blocking velocity and three with the lowest penetration velocity) are taken to calculate V. 50 The test value of the composite laminate is obtained by comparing the penetration velocity at different temperatures. The impact resistance of the composite laminate decreases with the increase of ambient temperature. The finite element abaqus program is used for simulation to analyze and calculate the V 50 The finite element simulation values ​​were obtained and compared with the test results. At the same time, the impact failure modes of composite material laminates at different temperatures were analyzed and calculated and compared with the composite material laminates after impact. The temperature effect was introduced into the high-speed impact of composite materials, simulating the service environment of the aircraft engine fan case, thereby improving the inclusiveness of the aircraft engine fan case.

[0146] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A composite material impact calculation method considering temperature influence, characterized in that: include: Step 1: Establish a dynamic constitutive model of polyimide fiber reinforced resin matrix composites considering the influence of temperature; Step 2: Conduct high-speed impact tests on the composite laminate at different temperatures, and collect bullet velocity and composite laminate damage as test sample data; Step 3: Take the three highest blocking velocities and the three lowest penetration velocities from the test sample data in step 2 to calculate V 50 The experimental value of Step 4: Establish a finite element model of composite laminates under high-speed bullet impact in a high-temperature environment in the Abaqus program; The specific steps of step 4 include: Step 41: Establish a dynamic constitutive model of polyimide fiber reinforced resin matrix composite material considering the temperature effect through VUMAT subroutine definition; The specific steps of step 41 include: Step 411: The influence of temperature on the performance of the composite laminate is considered in the display dynamic iteration step through the vumat subroutine, and the relationship between temperature and the elastic modulus of the composite laminate is: The relationship between temperature and the strength parameters of composite laminates is: Among them, E1, E2, E3, G 12 , G 13 and G 23 is the initial elastic modulus parameter of the composite laminate, the superscript T represents the temperature effect, T g is the dry glass transition temperature of the resin in the composite material, T is the current temperature, T0 is the room temperature, X t 、X c 、Y t 、Y c 、S 12 、S 13 and S 23 is the strength parameter of the composite material; Step 412: The influence of strain rate on the performance of the composite laminate is considered in the display dynamic iteration step through the vumat subroutine, and the dynamic enhancement factor of the strength of the composite laminate in different directions is: The relationship between the strain rate in different directions and the strength parameters of the composite laminate is: The dynamic enhancement factor of the elastic modulus of composite laminates in different directions is: The relationship between the strain rate in different directions and the elastic modulus of the composite laminate is: Among them, E and G are the initial elastic modulus parameters of the composite laminate, E rate and G rate are the elastic modulus parameters of the composite laminate after considering the strain rate effect, 1, 2, and 3 are E and E rate The subscripts 12, 23, and 31 are G and G rate The subscript of C rate is the strain rate effect parameter of the composite laminate, X T 、X C 、Y T 、Y C , Z T and Z C is the strength parameter of the composite laminate after considering the strain rate effect, is the strain rate, is the initial strain rate; Step 42: Using the three-dimensional Hashin failure criterion as the failure initiation criterion, a stiffness reduction degradation model is established by introducing damage variables based on the progressive damage accumulation theory and continuum damage mechanics. Step 5: Use the Abaqus program to simulate the high-speed impact test in step 2 and obtain V 50 The simulation value of .

2. The composite material impact calculation method considering temperature influence according to claim 1, characterized in that: The step 1 specifically includes: The stress-strain relationship of composite materials affected by temperature is established, and the elastic modulus and strength of composite materials affected by temperature and strain rate are corrected.

3. The composite material impact calculation method considering temperature influence according to claim 1, characterized in that: In step 3, V is calculated 50 The formula for the experimental value of is: in, is the arithmetic mean of the bullet velocity at the measuring point; v i is the velocity of the bullet that effectively hits the measuring point for the i-th round; x is the flight distance from the measuring point to the target; c x is the flight resistance coefficient of the projectile; ρ is the local air density; m f is the mass of the projectile; s is the frontal area of ​​the projectile.

4. The composite material impact calculation method considering temperature influence according to claim 1, characterized in that: The three-dimensional Hashin failure criterion in step 42 specifically includes: Fiber tensile failure mode: Fiber compression failure mode: Basic tensile failure modes: Basic compression failure modes: Among them, σ ij Represents the components of the stress tensor in the material coordinate system, X represents the material strength in the fiber direction, Y represents the material strength in the direction perpendicular to the fiber, subscripts T and C represent tensile load and compressive load respectively, S ij Represents the shear strength of the material, where i, j = 1, 2, 3; i ≠ j.

5. The composite material impact calculation method considering temperature influence according to claim 1, characterized in that: The step 5 specifically includes: Step 51: The abaqus main program calls the user subroutine VUMAT and passes the user input material parameters to the subroutine; Step 52: Correcting the material parameters of the composite laminate at the current temperature; Step 53: Calculate the strain rate of the current composite laminate, calculate and update the dynamic enhancement factors of the strength and elastic modulus of the composite laminate in each direction, and correct the material parameters of the composite laminate again; Step 54: Based on the defined dynamic constitutive model of the fiber reinforced resin matrix composite material considering the temperature effect, the stress and displacement of the elements divided on the composite laminate are updated and calculated; Step 55: Determine whether the elements divided on the composite laminate have failed according to the three-dimensional Hashin failure criterion. If failure has occurred, obtain the failed element and determine the failure mode. If fiber tensile failure has occurred, delete the failed element. Otherwise, degrade the material properties according to the stiffness degradation model. Step 56: Update and store state variables; Step 57: End the calculation and return to the main program to get V 50 The simulation value of .

6. The composite material impact calculation method considering temperature influence according to claim 1, characterized in that: The step 5 also includes comparing the damage analysis of the composite material laminate obtained by simulation with the actual damage diagram of the composite material laminate obtained by the high-speed impact test in step 2, and comparing V 50 The simulation value of V 50 The experimental values ​​were compared.

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