Method for enhancing toughness of hard and brittle material through twin microstructure confinement effect

Abstract

The invention discloses a method for enhancing toughness of a hard and brittle material through a twin micro-texture confinement effect, which comprises the following steps: S1, acquiring parameters of a strong, hard and brittle material matrix, establishing a three-point bending resistance simulation model of the strong, hard and brittle material, and determining simulation parameters; s2, carrying out three-point bending resistance simulation on the simulation model, completing the analysis of a three-point bending resistance stress field, and obtaining the optimal parameters of the twin microstructure space distribution; s3, performing ultrasonic cleaning on the surface-ground strong-hard-brittle material sample to obtain an original strong-hard-brittle material sample; and S4, drawing a laser processing pattern by a computer, and performing laser processing on the surface of the original strong hard and brittle material sample to obtain the hard and brittle material reinforced by the twin microstructure confinement effect. The twin microstructure prepared by the method has a space confinement effect, stress can be concentrated into the microstructure, and overall stress distribution on the surface of a material is dispersed, so that more potential energy is consumed, and the toughness of a hard and brittle material is improved.

Description

Technical Field

[0001] This invention belongs to the technical field of hard materials, and particularly relates to a method for enhancing the toughness of hard and brittle materials through the confinement effect of twin microtextures. Background Technology

[0002] Hard and brittle materials such as cemented carbide and ceramics are widely used in aerospace and metal processing, where they face extremely harsh environments. In particular, cutting tools used in metal processing may experience chipping or other problems when faced with difficult-to-machine materials due to insufficient toughness. The toughness of existing cemented carbide and ceramic materials is insufficient to meet the requirements.

[0003] Therefore, improving the toughness of hard and brittle materials has become an urgent need. In recent years, various toughening methods for hard and brittle materials have emerged, mainly focusing on improving sintering processes and adding reinforcing phases. Chinese patent document ZL201710105749.6 provides a method for preparing a TiN-based ceramic cutting tool material with HfC particle dispersion toughening reinforcement. This method improves the bending strength and mechanical properties of the material while maintaining its hardness by dispersing HfC in the ceramic matrix material. However, the methods of improving sintering processes and adding reinforcing phases have drawbacks such as complex preparation equipment and processes, high costs, and difficulty in industrialization.

[0004] This invention first proposes to prepare twinned microstructures on the surface of materials. By utilizing the stress concentration characteristics of the microstructures, stress is concentrated at the apex of the microtexture, dispersing the overall stress on the material surface. Furthermore, the spatial confinement effect of the microstructures is used to confine the stress within the microstructures, thereby consuming stress potential energy and extending the crack propagation path, thus improving the fracture toughness and mechanical properties of hard and brittle materials. Summary of the Invention

[0005] The technical problem to be solved by this invention is to address the shortcomings of existing methods by providing a method for enhancing the toughness of hard and brittle materials through the confinement effect of twinned microtextures. The twinned microstructures prepared by this method possess a spatial confinement effect, which can concentrate stress within the microstructure, disperse the overall stress distribution on the material surface, thereby consuming more potential energy and improving the toughness of hard and brittle materials.

[0006] To achieve the above-mentioned technical objectives, the technical solution adopted by the present invention is as follows:

[0007] A method for enhancing the toughness of hard and brittle materials through the confinement effect of twin microtextures includes the following steps:

[0008] S1. Obtain the physical property parameters, dimensional parameters, and geometric dimensional parameters of the spatial characteristic distribution of twin microstructures of the strong and brittle material matrix. Use the parameters to establish a three-point bending simulation model of the strong and brittle material and determine the simulation parameters.

[0009] S2. Perform three-point bending simulation on the simulation model, complete the analysis of the three-point bending stress field, and obtain the optimal parameters for the spatial distribution of the twin microstructure.

[0010] S3. After ultrasonic cleaning of the surface-ground hard and brittle material sample, the original hard and brittle material sample is obtained.

[0011] S4. Based on the optimal parameters of the spatial distribution of the twin microstructure, a laser processing pattern is drawn on the computer. The computer automatically transforms the drawn laser processing pattern and performs laser processing on the surface of the original hard and brittle material sample to obtain the twin microstructure. The twin microstructure is evenly distributed on the surface of the hard and brittle material sample according to the designed spacing, thereby obtaining a hard and brittle material enhanced by the confinement effect of the twin microtexture.

[0012] To optimize the above technical solution, the specific measures also include:

[0013] In step S1, the physical properties of the strong and brittle material matrix include Young's modulus, Poisson's ratio, density, and elastic modulus. The dimensional parameters include length, width, and thickness. The geometric dimensional parameters of the spatial distribution of the twin microstructure include microtexture length, width, depth, microtexture spacing, side angle, and microtexture arrangement.

[0014] In step S1, the parameters are imported into the Abaqus software to establish a three-point bending simulation model for strong and brittle materials. The simulation parameters include: defining the geometric material properties, defining the maximum principal strain, defining the fracture energy and damage evolution coefficient, defining the density, and mesh generation.

[0015] The specific method for step S2 is as follows:

[0016] Step S21, geometric modeling: Solidworks software is used to model the hard-brittle material sample, indenter, and left and right supports. Based on the different twin microstructure size characteristics, microstructures are set on the sample surface, with the microstructures evenly distributed on the upper and lower surfaces of the sample.

[0017] Step S22: Assemble the geometry: In Solidworks software, assemble the hard and brittle material sample, indenter, and left and right supports. Define that the upper surfaces of the left and right supports are tangent to the lower surface of the sample, and that their front faces coincide with the front face of the sample. Define that the lower surface of the indenter is tangent to the upper surface of the sample. In the "Width" option, select the lower surface of the indenter. Select the left and right end faces of the sample as the reference surfaces, so that the indenter is located in the middle of the sample.

[0018] Step S23: Import the assembly into Abaqus software: In Solidworks, save the assembly file as a ".x_t" file. Open Abaqus, select Import Assembly, select the corresponding ".x_t" file, and complete the import.

[0019] Step S24, define the material properties of the geometry: Create material "Material-1", and define Young's modulus, Poisson's ratio, and yield stress according to the hard-brittle material used; select Maxpe damage, and define the maximum principal strain, damage evolution type, fracture energy, damage evolution coefficient, and density; apply the created material "Material-1" to the new cross-section and assign it to the hard-brittle material sample, indenter, and left and right supports respectively.

[0020] Step S25, Define the analysis step: Create a general statics analysis step "Step-1", define the time length, maximum number of increment steps, initial increment step, and minimum increment step, and enable geometric nonlinearity.

[0021] Step S26, Define Contact: Define contact properties. The friction formula uses a penalty function. Set the contact between the lower surface of the indenter and the upper surface of the sample, and between the upper surfaces of the left and right supports and the lower surface of the sample, respectively. The lower surface of the indenter and the upper surfaces of the left and right supports are the primary surfaces, and the upper and lower surfaces of the sample are the secondary surfaces.

[0022] Step S27, Define constraints: Using the centers of the circles on the indenter and the left and right supports as reference points, set the indenter and the left and right supports as rigid body constraints. Using the centers of the left and right end faces of the sample as reference points, set the left and right end faces of the sample as coupling constraints.

[0023] Step S28, define boundary conditions: Create displacement / rotation boundary conditions, restrict all degrees of freedom of the indenter, set U2 to -1mm, and the rest to 0; restrict all degrees of freedom of the left and right supports to 0; restrict U2, UR1, and UR3 of the left and right end faces of the sample to 0, and leave the rest unrestricted.

[0024] Step S29, Mesh generation: The sample uses a C3D10 mesh, while the pressure head and left and right supports use a C3D8R mesh.

[0025] Step S210, Submit the job: Create and submit the job "Job-1". Based on "Job-1", perform a three-point bending simulation on the simulation model, complete the analysis of the three-point bending stress field, and obtain the optimal parameters for the spatial distribution of the twin microstructure.

[0026] The specific method of step S3 is as follows: the hard and brittle material is cut into block blanks using fast wire EDM, the ablation surface generated during wire EDM is removed by rough grinding using a surface grinder, and the surface scratches are removed by diamond polishing paste to obtain a smooth surface. The ground hard and brittle material sample is placed in a beaker containing anhydrous alcohol, and the surface oil and impurities are removed by ultrasonic cleaning. After standing, the residual alcohol is removed to obtain the original hard and brittle material sample.

[0027] The surface roughness of the ground hard and brittle material sample is Ra0.1-0.2.

[0028] The specific method of step S4 is as follows: draw the laser processing pattern on the computer according to the optimal parameters of the spatial distribution of the twin microstructure, the computer automatically transforms the drawn laser processing pattern, fixes the original hard and brittle material sample on the laser processing motion platform fixture, the computer drives the mechanical platform and the machine tool spindle, and uses infrared pulse laser to perform laser processing on the surface of the original hard and brittle material sample to obtain the twin microstructure. The twin microstructure is evenly distributed on the surface of the hard and brittle material sample according to the designed spacing, and the hard and brittle material is enhanced by the confinement effect of the twin microtexture.

[0029] The infrared pulsed laser power is 2-30W, the laser scanning path spacing ranges from 0.05mm to 0.15mm, and the laser spot overlap rate is 50%.

[0030] A method for enhancing the toughness of hard and brittle materials through the confinement effect of twin microtextures further includes step S5: conducting a three-point bending test on the hard and brittle material enhanced by the confinement effect of twin microtextures prepared in S4 using an electronic universal testing machine, and calculating the fracture toughness of the hard and brittle material enhanced by the confinement effect of twin microtextures.

[0031] The twin microstructures are 200-800 micrometers in length, 20-200 μm in width, and 10-200 μm in depth. The spacing between the twin microstructures is 100-800 μm, and the symmetrical distribution spacing is 50-400 μm.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] This invention overcomes the problem of insufficient mechanical properties such as toughness in existing hard and brittle materials, and develops a new twin microstructure toughening technology with confinement effect to improve the fracture toughness of hard and brittle materials.

[0034] This invention achieves active control of impact stress by changing the spatial distribution of microstructure, thereby improving the fracture toughness and other mechanical properties of strong and brittle materials. On the one hand, the toughness and mechanical properties are significantly improved, and the processing method is simple and the production cost is low. On the other hand, this manufacturing method does not require the addition of reinforcing phases to change the phase composition of the material. By controlling the size and spatial distribution of the microstructure, the impact stress distribution is actively controlled, which hinders the distribution of stress and thus improves the toughness of strong and brittle materials.

[0035] The confinement effect of the twinned microstructures in this invention endows strong and brittle materials with excellent fracture toughness. The optimal mechanical properties are achieved when the twinned microstructures have a length of 400 μm, a width of 100 μm, a depth of 100 μm, a spacing of 70 μm between twinned microstructures, and a symmetrical distribution spacing of 200 μm. The fracture toughness, flexural strength, and hardness of the strong and brittle material are 10.15 MPa·m. 1 / 21840.43MPa, 15.68GPa (commercially available YG8 cemented carbide plate). Attached Figure Description

[0036] Figure 1 This is a distribution diagram of the twin microstructures designed in this invention on the surface of a hard and brittle material;

[0037] Figure 2 This is a finite element simulation result of the stress distribution during the three-point bending process of cemented carbide material;

[0038] Figure 3 These are images showing the fracture toughness changes of the cemented carbide material prepared according to the present invention, where the angle on the horizontal axis is the angle between the twin microstructure edge and the sample edge. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this application clearer, the application is described and illustrated below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application. All other embodiments obtained by those skilled in the art based on the embodiments provided in this application without inventive effort are within the scope of protection of this application.

[0040] Obviously, the accompanying drawings described below are merely some examples or embodiments of this application. Those skilled in the art can apply this application to other similar scenarios based on these drawings without any inventive effort. Furthermore, it is understood that although the efforts made in this development process may be complex and lengthy, for those skilled in the art related to the content disclosed in this application, any changes to design, manufacturing, or production based on the technical content disclosed in this application are merely conventional technical means and should not be construed as insufficient disclosure of the content of this application.

[0041] The cemented carbide and alumina ceramic samples used in the examples were commercially available YG8 cemented carbide plates and alumina ceramic plates.

[0042] Example 1:

[0043] Mechanical properties of YG8 cemented carbide plate: fracture toughness 8.5 MPa·m 1 / 2 Flexural strength is 1500MPa, and hardness is 15GPa.

[0044] A method for enhancing the toughness of cemented carbide plates through the confinement effect of twinned microstructures is disclosed. The optimal mechanical properties are achieved when the twinned microstructures have a length of 400 μm, a width of 100 μm, a depth of 100 μm, a spacing of 70 μm between twinned microstructures, a symmetrical distribution spacing of 200 μm, and an angle of 45° between the edges of the twinned microstructures and the sample edge. The YG8 cemented carbide plate exhibits fracture toughness, bending strength, and hardness of 10.15 MPa·m. 1 / 2 1840.43MPa, 15.68GPa.

[0045] The preparation steps are as follows:

[0046] 1. Obtain the physical property parameters, dimensional parameters, and spatial characteristic distribution geometric dimension parameters of the YG8 cemented carbide plate matrix, and import the obtained parameters into Abaqus software to establish a simulation model of the three-point bending simulation process of cemented carbide material, and determine the simulation parameters;

[0047] 2. Based on the simulation model, the stress field distribution during the three-point bending process is calculated, and a stress field distribution cloud map is obtained; the specific process is as follows:

[0048] Step S21: Perform geometric modeling: Model the twin microstructure sample, indenter, and left and right supports using Solidworks software. The sample is generally rectangular in shape, with overall dimensions of 20×4×5mm. Based on the different dimensional characteristics of the twin microstructures, microstructures are set on the surface of the sample, and the microstructures are evenly distributed on the upper and lower surfaces of the sample. The indenter and left and right supports are both semi-cylinders with a diameter of 1mm and a length of 5mm.

[0049] Step S22: Assemble the geometry: Assemble the twin microstructure sample, indenter, and left and right supports in Solidworks software. Define the upper surfaces of the left and right supports to be tangent to the lower surface of the sample, and the front faces to coincide with the front faces of the sample, with a support spacing of 16mm; define the lower surface of the indenter to be tangent to the upper surface of the sample, select the lower surface of the indenter in the "Width" option, and select the left and right end faces of the sample as the reference surface, so that the indenter is located in the middle of the sample.

[0050] Step S23: Import the assembly into Abaqus software: In Solidworks, save the assembly file as a ".x_t" file. Open Abaqus, select Import Assembly, select the corresponding ".x_t" file, and complete the import.

[0051] Step S24, define the geometric material properties: Create material "Material-1" using YG8 cemented carbide, define Young's modulus as 510000 MPa, Poisson's ratio as 0.22; define yield stress as 2300 MPa; select Maxpe damage, define maximum principal strain as 0.3, damage evolution type as energy, fracture energy as 4 mJ, damage evolution coefficient as 1E-05; define density as 1.5E10T / mm3. Apply the created material "Material-1" to the new cross-section and assign it to the twin microstructure sample, indenter, and left and right supports respectively.

[0052] Step S25, Define the analysis step: Create a static general analysis step "Step-1", define the time length as 10, the maximum number of increment steps as 1000, the initial increment step as 0.001, the minimum increment step as 1E-45, and enable geometric nonlinearity.

[0053] Step S26, Define Contact: Define contact properties, use a penalty function for the friction formula, and set the friction coefficient to 0.3. Set the contact between the lower surface of the indenter and the upper surface of the sample, and between the upper surfaces of the left and right supports and the lower surface of the sample, respectively, with the lower surface of the indenter and the upper surfaces of the left and right supports as the primary surfaces, and the upper and lower surfaces of the sample as secondary surfaces.

[0054] Step S27, Define constraints: Using the centers of the circles on the indenter and the left and right supports as reference points, set the indenter and the left and right supports as rigid body constraints. Using the centers of the left and right end faces of the sample as reference points, set the left and right end faces of the sample as coupling constraints.

[0055] Step S28, define boundary conditions: create displacement / rotation boundary conditions. Restrict all degrees of freedom of the indenter, set U2 to -1mm, and the rest to 0; restrict all degrees of freedom of the left and right supports to 0; restrict U2, UR1, and UR3 of the left and right end faces of the sample to 0, and leave the rest unrestricted.

[0056] Step S29, Mesh Generation: The sample uses a C3D10 mesh with a global seed size of 0.5mm, and a local seed size of 0.01mm is set on the groove surface. The pressure head and left and right supports use a C3D8R mesh with a mesh size of 0.5mm.

[0057] Step S210, Submit the job: Create and submit the job "Job-1", perform a three-point bending simulation based on "Job-1", complete the stress field distribution calculation during the three-point bending process, and obtain the stress field distribution cloud map.

[0058] 3. Cut the cemented carbide material into 30mm*30mm*4mm block blanks using fast wire EDM. Use a surface grinder to rough grind the surface to remove the ablation caused by the wire EDM, and use diamond polishing paste to remove the surface scratches to obtain a smooth surface.

[0059] 4. Place the ground cemented carbide sample into a beaker containing anhydrous alcohol, and clean it with ultrasound for 15 minutes to remove surface oil and other impurities. Let it stand for 5 minutes to remove residual alcohol and obtain the original cemented carbide sample.

[0060] 5. Fix the original cemented carbide sample on the laser processing motion platform fixture, draw the laser processing pattern on the computer, drive the mechanical platform and machine tool spindle, and the computer automatically transforms the drawn laser processing pattern to perform laser processing;

[0061] 6. The surface of the cemented carbide sample was laser-processed using an infrared pulsed laser with a wavelength of 1064nm to obtain twinned microstructures. The laser power was 20W, the laser scanning path spacing range was 0.1mm, and the laser spot overlap rate was 50%. The twinned microstructures were uniformly distributed on the surface of the cemented carbide sample according to the designed spacing, thus obtaining a cemented carbide plate reinforced by the confinement effect of twinned microtextures.

[0062] 7. A hard alloy plate with twin microtextured confinement effect was prepared according to the single-sided notched beam method. Three-point bending resistance test was carried out by electronic universal testing machine, and mechanical properties such as fracture toughness were calculated.

[0063] The prepared twinned microtexture confinement effect reinforced cemented carbide plate was ground and polished to prepare a 3mm×4mm×30mm sample. Its mechanical properties were measured as follows: fracture toughness, bending strength, and hardness were all 10.15 MPa·m. 1 / 2 1840.43MPa, 15.68GPa.

[0064] Example 2:

[0065] Mechanical properties of alumina ceramic materials: fracture toughness 3.5 MPa·m 1 / 2 The bending strength is 650MPa and the hardness is 18GPa.

[0066] A method for enhancing alumina ceramic plates through the confinement effect of twinned microstructures is disclosed. The optimal mechanical properties are achieved when the twinned microstructures have a length of 400 μm, a width of 100 μm, a depth of 100 μm, a spacing of 70 μm between twinned microstructures, a symmetrical distribution spacing of 200 μm, and an angle of 45° between the edges of the twinned microstructures and the sample edge. The fracture toughness of the alumina ceramic material is 5.12 MPa·m. 1 / 2 Flexural strength 754.2 MPa, hardness 18.2 GPa

[0067] The preparation steps are as follows:

[0068] 1. Obtain the physical properties, dimensional parameters, and spatial characteristic distribution geometric dimensional parameters of the alumina ceramic matrix, and import the obtained parameters into Abaqus software to establish a simulation model of the three-point bending simulation process of alumina ceramic materials, and determine the simulation parameters;

[0069] 2. The stress field distribution during the three-point bending process is calculated based on the simulation model to obtain the stress field distribution cloud map. The specific process of this step is similar to the corresponding process in the first embodiment. Please refer to the relevant steps of YG8 cemented carbide.

[0070] 3. Cut the alumina ceramic material into 30mm*30mm*4mm block blanks using a fast-moving internal circular slicer. Use a surface grinder to rough grind the ablated surface generated during the internal circular slicer cutting process, and use diamond grinding paste to remove the surface scratches to obtain a smooth surface.

[0071] 4. Place the ground alumina ceramic sample into a beaker containing anhydrous alcohol, and clean it with ultrasound for 15 minutes to remove surface oil and other impurities. Let it stand for 5 minutes to remove residual alcohol and obtain the original alumina ceramic sample.

[0072] 5. Fix the alumina ceramic sample on the laser processing motion platform fixture, draw the laser processing pattern on the computer, drive the mechanical platform and machine tool spindle, and the computer automatically transforms the drawn laser processing pattern to perform laser processing;

[0073] 6. The surface of the alumina ceramic sample was laser-processed using an infrared pulsed laser with a wavelength of 1064nm to obtain twinned microstructures. The laser power was 22W, the laser scanning path spacing range was 0.1mm, and the laser spot overlap rate was 50%. The twinned microstructures were uniformly distributed on the surface of the alumina ceramic sample according to the designed spacing, thus obtaining an alumina ceramic plate enhanced by the confinement effect of twinned microtextures.

[0074] 7. An alumina ceramic plate reinforced by the twin microtexture confinement effect was prepared according to the single-sided notched beam method. Three-point bending resistance test was carried out by an electronic universal testing machine, and mechanical properties such as fracture toughness were calculated.

[0075] The alumina ceramic plate enhanced by the twin microtexture confinement effect was ground and polished to prepare ceramic strips of 3mm×4mm×30mm. Its mechanical properties were measured as follows: fracture toughness, flexural strength, and hardness were all 5.12 MPa·m. 1 / 2 754.2 MPa, 18.2 GPa.

[0076] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the embodiments described above. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A method for enhancing the toughness of hard and brittle materials through the confinement effect of twin microtextures, characterized in that, Includes the following steps: S1. Obtain the physical property parameters, dimensional parameters, and geometric dimensional parameters of the spatial characteristic distribution of twin microstructures of the strong and brittle material matrix. Use the parameters to establish a three-point bending simulation model of the strong and brittle material and determine the simulation parameters. S2. Perform three-point bending simulation on the simulation model, complete the analysis of the three-point bending stress field, and obtain the optimal parameters for the spatial distribution of the twin microstructure. S3. After ultrasonic cleaning of the surface-ground hard and brittle material sample, the original hard and brittle material sample is obtained. S4. Based on the optimal parameters of the spatial distribution of the twin microstructure, a laser processing pattern is drawn on the computer. The computer automatically transforms the drawn laser processing pattern and performs laser processing on the surface of the original hard and brittle material sample to obtain the twin microstructure. The twin microstructure is evenly distributed on the surface of the hard and brittle material sample according to the designed spacing, thereby obtaining a hard and brittle material enhanced by the confinement effect of the twin microtexture.

2. The method for enhancing the toughness of hard and brittle materials through the confinement effect of twin microtextures according to claim 1, characterized in that, In step S1, the physical properties of the strong and brittle material matrix include Young's modulus, Poisson's ratio, density, and elastic modulus. The dimensional parameters include length, width, and thickness. The geometric dimensional parameters of the spatial distribution of the twin microstructure include microtexture length, width, depth, microtexture spacing, side angle, and microtexture arrangement.

3. The method for enhancing the toughness of hard and brittle materials through the confinement effect of twin microtextures according to claim 1, characterized in that, In step S1, the parameters are imported into the Abaqus software to establish a three-point bending simulation model for strong and brittle materials. The simulation parameters include: defining the geometric material properties, defining the maximum principal strain, defining the fracture energy and damage evolution coefficient, defining the density, and mesh generation.

4. The method for enhancing the toughness of hard and brittle materials through the confinement effect of twin microtextures according to claim 1, characterized in that, The specific method for step S2 is as follows: Step S21, geometric modeling: Solidworks software is used to model the hard-brittle material sample, indenter, and left and right supports. Based on the different twin microstructure size characteristics, microstructures are set on the sample surface, with the microstructures evenly distributed on the upper and lower surfaces of the sample. Step S22: Assemble the geometry: In Solidworks software, assemble the hard and brittle material sample, indenter, and left and right supports. Define that the upper surfaces of the left and right supports are tangent to the lower surface of the sample, and that their front faces coincide with the front face of the sample. Define that the lower surface of the indenter is tangent to the upper surface of the sample. In the "Width" option, select the lower surface of the indenter. Select the left and right end faces of the sample as the reference surfaces, so that the indenter is located in the middle of the sample. Step S23: Import the assembly into Abaqus software: In Solidworks, save the assembly file as a ".x_t" file. Open Abaqus, select "Import Assembly," choose the corresponding ".x_t" file, and complete the import. Step S24, define the material properties of the geometry: Create material "Material-1", and define Young's modulus, Poisson's ratio, and yield stress according to the hard-brittle material used; select Maxpe damage, and define the maximum principal strain, damage evolution type, fracture energy, damage evolution coefficient, and density. Apply the created material "Material-1" to the new cross-section and assign it to the hard-brittle material sample, indenter, and left and right supports respectively. Step S25, Define the analysis step: Create a general statics analysis step "Step-1", define the time length, maximum number of increment steps, initial increment step, and minimum increment step, and enable geometric nonlinearity. Step S26, Define Contact: Define contact properties. The friction formula uses a penalty function. Set the contact between the lower surface of the indenter and the upper surface of the sample, and between the upper surfaces of the left and right supports and the lower surface of the sample, respectively. The lower surface of the indenter and the upper surfaces of the left and right supports are the primary surfaces, and the upper and lower surfaces of the sample are the secondary surfaces. Step S27, Define constraints: Using the centers of the circles on the indenter and the left and right supports as reference points, set the indenter and the left and right supports as rigid body constraints. Using the centers of the left and right end faces of the sample as reference points, set the left and right end faces of the sample as coupling constraints. Step S28, define boundary conditions: Create displacement / rotation boundary conditions, restrict all degrees of freedom of the indenter, set U2 to -1mm, and the rest to 0; restrict all degrees of freedom of the left and right supports to 0; restrict U2, UR1, and UR3 of the left and right end faces of the sample to 0, and leave the rest unrestricted. Step S29, Mesh generation: The sample uses a C3D10 mesh, while the pressure head and left and right supports use a C3D8R mesh. Step S210, Submit the job: Create and submit the job "Job-1". Based on "Job-1", perform a three-point bending simulation on the simulation model, complete the analysis of the three-point bending stress field, and obtain the optimal parameters for the spatial distribution of the twin microstructure.

5. A method for enhancing the toughness of hard and brittle materials through the confinement effect of twin microtextures according to claim 1, characterized in that, The specific method of step S3 is as follows: the hard and brittle material is cut into block blanks using fast wire EDM, the ablation surface generated during wire EDM is removed by rough grinding using a surface grinder, and the surface scratches are removed by diamond polishing paste to obtain a smooth surface. The ground hard and brittle material sample is placed in a beaker containing anhydrous alcohol, and the surface oil and impurities are removed by ultrasonic cleaning. After standing, the residual alcohol is removed to obtain the original hard and brittle material sample.

6. A method for enhancing the toughness of hard and brittle materials through the confinement effect of twin microtextures according to claim 5, characterized in that, The surface roughness of the ground hard and brittle material sample is Ra0.1-0.

2.

7. A method for enhancing the toughness of hard and brittle materials through the confinement effect of twin microtextures according to claim 1, characterized in that, The specific method of step S4 is as follows: draw the laser processing pattern on the computer according to the optimal parameters of the spatial distribution of the twin microstructure, the computer automatically transforms the drawn laser processing pattern, fixes the original hard and brittle material sample on the laser processing motion platform fixture, the computer drives the mechanical platform and the machine tool spindle, and uses infrared pulse laser to perform laser processing on the surface of the original hard and brittle material sample to obtain the twin microstructure. The twin microstructure is evenly distributed on the surface of the hard and brittle material sample according to the designed spacing, and the hard and brittle material is enhanced by the confinement effect of the twin microtexture.

8. A method for enhancing the toughness of hard and brittle materials through the confinement effect of twin microtextures according to claim 7, characterized in that, The infrared pulsed laser power is 2-30W, the laser scanning path spacing ranges from 0.05mm to 0.15mm, and the laser spot overlap rate is 50%.

9. A method for enhancing the toughness of hard and brittle materials through the confinement effect of twin microtextures according to claim 1, characterized in that, The method also includes step S5: the twin microtexture confinement effect enhanced hard and brittle material prepared in S4 is subjected to a three-point bending test using an electronic universal testing machine, and the fracture toughness of the twin microtexture confinement effect enhanced hard and brittle material is calculated.

10. A method for enhancing the toughness of hard and brittle materials through the confinement effect of twin microtextures according to claim 1, characterized in that, The twin microstructures are 200-800 micrometers in length, 20-200 μm in width, and 10-200 μm in depth. The spacing between the twin microstructures is 100-800 μm, and the symmetrical distribution spacing is 50-400 μm.

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