Wear prediction method based on macro and micro fatigue fracture mechanics of material
By using a wear testing device and method based on the macro- and micro-fatigue fracture mechanics of materials, and combining macro-crack propagation and micro-crack evolution, the problems of long test cycles and low prediction accuracy of material wear life have been solved, and efficient and scientific prediction of wear particle generation has been achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA NORTH VEHICLE RES INST
- Filing Date
- 2026-02-09
- Publication Date
- 2026-05-26
AI Technical Summary
Existing technologies have long material wear life testing cycles, lack guidance from microscopic mechanism models, and cannot accurately predict the number and distribution of wear particles.
A wear testing device and prediction method based on the macro- and micro-fatigue fracture mechanics of materials are adopted. Combining macro-crack propagation and micro-crack evolution, wear particles are monitored in real time through a loading device and a particle analyzer, and the wear life is calculated using the energy release rate.
It significantly shortens the wear life prediction cycle, improves prediction accuracy, and can scientifically and reasonably describe the quantity and size distribution of particles generated during the wear process.
Smart Images
Figure CN122084432A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of material wear and fatigue life prediction technology, and particularly relates to a wear prediction method and testing device based on the macro- and micro-scale fatigue fracture mechanics of materials. Background Technology
[0002] During the service life of engineering components such as vehicle tires and rail brake pads, material wear and particulate matter generation are among the main causes of failure. Accurately predicting the wear life of materials has always been a cutting-edge research topic. Furthermore, the large amount of particulate matter emitted during wear also causes air and water pollution. Studies show that an average of about 0.8 kg of tire particles are emitted into the environment per person per year. With a huge global vehicle fleet, this problem causes significant pollution hazards to air and water. Currently, there is no reasonable method to accurately predict the quantity and distribution of wear particles.
[0003] Traditional wear life assessment methods largely rely on long-term experiments and empirical models. For example, the well-known Arcard wear law assumes that wear volume is directly proportional to load and sliding distance, and inversely proportional to material hardness, using empirical coefficients to fit the wear amount. These methods typically depend on long-cycle wear resistance tests or empirical formulas for estimation. Typical experiments, such as pin-disc wear testing machines, require subjecting samples to repeated friction over long periods and distances under a certain load to measure wear and extrapolate life. Such tests are not only time-consuming and costly, but also have limited predictive accuracy due to potential differences between test conditions and actual operating conditions. When using empirical formulas (such as the linear accumulation method based on the wear rate constant) for life estimation, they lack consideration of internal damage accumulation and crack propagation mechanisms, resulting in insufficient accuracy. Furthermore, these macroscopic models treat wear as a loss of overall material volume, failing to reveal the formation of microcracks and the size distribution of wear particles during the wear process, and even less able to predict the concentration of particles generated by wear. In recent years, some researchers have proposed treating the wear process as a material fracture mechanics problem, explaining wear using energy methods (such as the wear fracture model proposed by Akono et al., and the classic Suh wear theory). These models explain the fracture mechanism of abrasive wear to some extent, but they have not yet been able to correlate wear fracture behavior with the number and size distribution of released particles. Therefore, there is a lack of a macro-micro combined mechanistic model in the prior art to quantitatively describe the relationship between material wear and particle generation.
[0004] Therefore, there is an urgent need in the current technology for a material wear life prediction method and corresponding experimental device based on reliable mechanical theory. On the one hand, this method should be able to combine the macroscopic crack propagation and microscopic crack evolution of materials to quantitatively describe the relationship between energy release and particle formation during wear; on the other hand, this method should obtain the required parameters through simplified and efficient experiments, significantly shortening the wear life prediction cycle. Summary of the Invention
[0005] The technical problem to be solved by this invention is the long testing cycle of material wear life and the lack of guidance from microscopic mechanism models.
[0006] To solve the above-mentioned technical problems, the specific technical solution of the present invention is as follows: A wear testing device based on the macro- and micro-scale fatigue fracture mechanics of materials includes: a base plate 1 and a guide rail frame 2 mounted on the base plate 1; the guide rail frame 2 is provided with a vertical guide rail 3 and a slider 4 that slides up and down along the guide rail 3; a cantilever support 6 is fixed on the slider 4, a loading device frame 5 is mounted on the cantilever support 6, and a loading and mechanical measurement assembly device 7 is assembled on the loading device frame 5, the front end of the loading and mechanical measurement assembly device 7 is provided with a loading head 8, the surface of the loading head 8 is covered with test sandpaper; a stepper motor mounting bracket 14 is fixedly mounted on the base plate 1 via a support 15, the stepper motor mounting bracket 14... A stepper motor 13 is installed on the 4th plate. The output shaft of the stepper motor 13 drives the rotating wheel 10 to rotate through a pin connection. The outer peripheral surface of the rotating wheel 10 is covered with the test wear material sample 9. The loading head 8 can press against the surface of the test material 9 on the rotating wheel 10 in the vertical direction with the vertical force. The rotation direction of the rotating wheel 10 is parallel to the plane of the base plate 1. The test device is provided with a particle isolation cover 16 to enclose the wear test area. The particle isolation cover 16 has a test hole 11. The probe of the particle testing device 12 extends into the particle isolation cover 16 through the test hole 11 to collect wear particles.
[0007] Furthermore, the type of sandpaper used on the loading head 8 is selected based on the roughness parameters of the actual road surface.
[0008] Furthermore, the rotational speed of the stepper motor 13 is set to correspond to the simulated actual vehicle speed.
[0009] Furthermore, the loading and mechanical measurement assembly 7 integrates a force sensor, which can measure the tangential and vertical forces experienced by the loading head 8 during the friction process, and transmit the data to the data recording system.
[0010] Furthermore, the particle testing device 12 is a particle size analyzer.
[0011] This invention also provides a wear prediction method based on the macro- and micro-scale fatigue fracture mechanics of materials. The method is implemented using the testing device described in claim 1 and includes the following steps: Step 1: Select test parameters based on actual working conditions, and convert the actual working load into the required tangential force per particle for the test. and vertical force The width of road surface particles is calculated based on the road surface unevenness and roughness. With particle length Select with the and Sandpaper of corresponding roughness is used as the abrasive medium, and the rotational speed of stepper motor 13 is set to the equivalent value of vehicle speed. Step 2: Conduct the wear test according to the selected test parameters. Fix the wear material sample 9 to the outer surface of the rotating wheel 10, cover the selected sandpaper on the loading head 8 of the loading and mechanical measurement device 7, and set the vertical load. Under the action of the loading head 8, the loading head 8 is pressed against the surface of the test material 9; the stepper motor 13 is started to drive the rotating wheel 10 to rotate at the equivalent vehicle speed, so that the sandpaper on the loading head 8 and the surface of the test material 9 will undergo relative frictional motion to generate wear; the particle testing device 12 extends into the test hole 11 of the particle isolation cover 16 through the particle testing device 12 to collect the particles generated by wear and measure the particle size distribution, so as to obtain the average particle size and particle size variance of the wear particles; Step 3: Calculate the total energy release rate according to the following formula. :
[0012] Among them, under plane stress conditions Under plane strain conditions Poisson's ratio of the material; For the width of road surface particles, For the length of road surface particles, The Young's modulus of the test material. The equivalent Young's modulus of the cracked material; For the tangential force per particle, The vertical force per particle; The length of the macroscopic crack; Microcrack density; The average particle size of the wear particles. The variance of wear particle size; Step 4: Based on the calculated total energy release rate Find the fatigue crack propagation rate for the corresponding material; Step 5: Estimate the wear life of the material based on the fatigue crack propagation rate and the critical crack length of the material.
[0013] Step 4 further involves: calculating the... Substitute the fatigue crack propagation characteristic curve of the material into the curve to determine the corresponding fatigue crack propagation rate. The crack propagation characteristics are obtained through prior material fatigue tests.
[0014] Furthermore, the type of sandpaper used on the loading head 8 is selected based on the roughness parameters of the actual road surface.
[0015] The present invention has the following advantages: Simple and low-cost device: The experimental device has a very simple structure, is easy to build and is inexpensive; High testing efficiency: The test time is greatly shortened. Wear life tests that used to take several days or even months can now be completed in just about 5 minutes. Solid theoretical foundation: This method is based on the macroscopic and microscopic fatigue fracture mechanics model of materials, which has a profound theoretical foundation and wide applicability, and can be applied to the wear life prediction of different organic materials; A more scientific approach is taken into account for particle distribution: The influence of wear particle size distribution on energy release is considered in the energy calculation, making the prediction results more scientific and reasonable. Attached Figure Description
[0016] Figure 1 This is a flowchart of the wear prediction method of the present invention; Figure 2 This is a schematic diagram of the wear prediction testing device of the present invention; Figure 3 Figure 1 shows the results of wear tests on materials with different Young's moduli. Figure 4 The results of wear tests with varying loading conditions are shown in the figure. Wherein: 1-base plate; 2-guide rail frame; 3-guide rail; 4-slider; 5-loading device frame; 6-cantilever support; 7-loading and mechanical measurement assembly device; 8-loading head; 9-tested wear material; 10-rotating wheel; 11-test hole; 12-particle testing device; 13-stepper motor; 14-stepper motor mounting frame; 15-support; 16-particle isolation cover. Detailed Implementation
[0017] To better understand the purpose, structure, and function of this invention, the invention will be described in further detail below with reference to the accompanying drawings.
[0018] like Figure 2As shown, the supporting wear prediction test device provided by this invention includes a simple sandpaper friction and wear test frame, which can simulate the wear of vehicle tires and road surfaces in the laboratory. It also includes a mechanical measurement assembly 7, a loading head 8, a test wear material sample 9, a rotating wheel 10, a test hole 11, a particle testing device 12, a stepper motor 13, a stepper motor mounting bracket 14, a support column 15, and a particle isolation cover 16. The base plate 1 is placed horizontally on the ground, and a guide rail frame 2 is fixedly installed on the base plate 1. A guide rail 3 is vertically mounted on the guide rail frame 2, and a slider 4 is slidably connected to the guide rail 3, allowing the slider 4 to slide vertically up and down along the guide rail 3. A cantilever support column 6 is fixed to the slider 4, and a loading device frame 5 is mounted on the cantilever support column 6. The loading device frame 5 is equipped with the loading and mechanical measurement assembly 7. The front end of the loading and mechanical measurement assembly 7 has a loading head 8, and sandpaper (as an abrasive) for wear testing is attached to the bottom surface of the loading head 8. On the other side of the device, a stepper motor mounting bracket 14 is fixed via a support column 15, and a stepper motor 13 is mounted on the stepper motor mounting bracket 14. The output shaft of the stepper motor 13 is connected to the center of the rotating wheel 10 via a pin, and the rotation axis of the rotating wheel 10 is parallel to the plane of the base plate 1. After the stepper motor 13 is powered on, it drives the rotating wheel 10 to rotate around its axis. The outer circumferential surface of the rotating wheel 10 is used to mount the test wear material sample 9, which can be firmly mounted on the surface of the rotating wheel by means of adhesion or mechanical fixation. Driven by the loading and mechanical measurement assembly device 7, the loading head 8 can move vertically along the guide rail 3 and press against the test material 9 on the surface of the rotating wheel 10 in the vertical direction, thereby applying a vertical load to the test sample. When the stepper motor 13 drives the rotating wheel 10 to rotate at a certain speed, the sandpaper on the loading head 8 will slide against the surface of the material sample 9, simulating the wear effect in actual working conditions. A particle isolation hood 16 is installed around the test area to enclose the contact area between the rotating wheel and the loading head, and is used to collect the particles generated by wear. The particle isolation hood 16 has test holes 11, which allow a particle testing device 12 (such as a particle size analyzer probe) to be inserted into the isolation hood to collect wear particles in real time. The loading and mechanical measurement device 7 integrates force sensors, which can measure the tangential force and vertical force experienced by the loading head 8 during friction, and transmit the data to the data recording system.
[0019] Using the aforementioned testing equipment, wear prediction tests can be performed efficiently. Specifically, the process can be as follows: First, determine the test parameters based on the actual application scenario, for example, converting the vehicle load into the tangential force of sandpaper particles. and vertical force A sandpaper with a surface roughness corresponding to the road surface is selected and placed on the loading head 8, and the speed of the stepper motor 13 is set to simulate the vehicle speed. Then, the test material sample 9 is fixed on the surface of the rotating wheel 10, and a set vertical load is applied by the loading device 7 to press the sandpaper firmly onto the sample surface. The stepper motor 13 is started to drive the rotating wheel 10 to rotate at the set speed. After a short period of continuous friction (e.g., several minutes), a certain degree of wear can be generated on the material surface, equivalent to the amount of wear accumulated over a longer period of time under actual working conditions. During the test, the loading and mechanical measurement device 7 continuously monitors and records the data. and The particle testing device 12 samples and tests the wear particles inside the isolation cover 16 to obtain the particle size distribution data of the wear particles, including the average particle size. and particle size variance The above test data will be used for subsequent wear life prediction calculations.
[0020] 1. Macroscopic crack energy release rate The grinding process of sandpaper on a material can be equated to forming a surface with a width of approximately [missing information]. , length is The depth is approximately Surface cracks (or grooves). When loading head 8 applies tangential force per particle. and vertical force At that time, the surface crack will generate a driving force for propagation.
[0021] Given the structural geometry and external loads, the boundary value problem can be expressed in stress form as follows: (2) Satisfy boundary conditions
[0022] in, For Cauchy stress tensor, For volumetric stress, The normal vector outside the stress boundary. Let be the traction force vector. The two governing equations in equation (1) correspond to the Beltrami stress compatibility equation and the stress balance equation, respectively. After the elastic field is completely determined, the energy release rate can be calculated using the path-independent J integral.
[0023] exist A set of horizontal and vertical boundary traction forces are applied to the left end of the overburden layer. and According to Saint Vincent's principle, in At the boundary, the stress boundary condition and the moment boundary condition can be expressed in integral form as follows: (3) (4) arbitrary cross section Above, by stress boundary External forces at the location The generated torque, and the internal stress on that cross section The resulting torques must be balanced, that is: (5) in, To be from the cross section To stress boundary Position vector, Let be the vector from the centroid of the cross section to any point on that cross section. The corresponding force equilibrium condition is: (6) By solving the above equations, we can obtain the stress balance equations: (7) To solve the above relationship, the stress vector flow function is defined as follows: (8) The above formula is based on the stress form, and its governing equation is the Beltrami–Michell stress compatibility equation. (9) in, This is a special case of volumetric stress, due to the assumption made in the semi-inverse method. Substituting the stress components into equation (9) yields: (10) Integrating, we obtain the governing equations of the stream function: (11) Where the integration constant This characterizes the torsional effect in the Prandtl stress function. If the cross-section is highly symmetrical and the shear center coincides with the centroid, this constant is zero, meaning that there is no warping effect during cross-section deformation.
[0024] The final stream function can be obtained by solving the partial differential equation: (12) The stress components can be obtained from the stream function solution: (13) Using the Filon averaging method in the generalized plane stress problem, the boundary value problem can be approximated as a plane problem: (14) The above stress components are based on the assumptions This refers to the plane stress condition. If we introduce... This can then be transformed into a plane strain condition, where the strain... It will be established.
[0025] The difference between plane stress and plane strain conditions is reflected in the displacement field formula: (27) in, Corresponding plane stress condition, Corresponding plane strain condition; , Let be the rigid body displacement function; Let the Airy stress function satisfy: (28) For a differentiable Airy stress function, there exists a corresponding harmonic function. ,satisfy: (29) Based on the above requirements, a trial solution is constructed: (30) At this point, analytical solutions for both the displacement field and the stress field have been obtained.
[0026] The energy release rate of macroscopic cracks is determined by the new crack surface. The formation of which is caused by, among which The length of the crack. The outer perimeter of the cutting edge of the tool. Energy release rate. Calculated by J integral: (31) in, For closed boundaries, .Will Divided into two parts: (32) Strain energy density Hooke's Law defines it as follows: (33) The explicit calculation of the J integral can be obtained from equation (35): (34) The overall strain energy can also be calculated as follows: (35) At this point, the analytical solution of the boundary value problem, the displacement and stress field distribution, the energy release rate, and the total strain energy calculation have all been completed.
[0027] 2. Additional energy release rate of microcracks The material contains numerous randomly distributed microcracks. Under repeated frictional loading, these microcracks continuously initiate and propagate, reducing the overall stiffness of the material and generating additional energy release. To quantify the impact of microcracks on energy release, we adopt the concept of equivalent elastic modulus. According to the self-consistent method, the equivalent Young's modulus of a material containing random microcracks is... By the number of microcracks per unit Characterized by: the unit number of microcracks is defined as the number of microcracks per unit volume. The introduction of a large number of microcracks reduces the equivalent modulus of the material. Through derivation, the equivalent Young's modulus of a cracked body can be expressed as: (36) in The equivalent Poisson's ratio for cracked bodies is given by: Equivalent density of microcracks When a microcrack propagates further under load, the additional strain energy released by the material can be estimated by differentiating the change in the effective modulus. Under force-controlled loading, the additional energy release rate is defined as the energy released by the material per unit area of microcrack propagation, i.e. (37) If the cracking process is displacement-controlled, a negative sign should be added before this equation. Using the chain rule, we can obtain: (38) (39) The additional energy release rate can be expressed as: (40) in, Corresponding plane stress condition, Corresponding plane strain condition.
[0028] Further consideration, the first The characteristic length of a microcrack can be expressed as: ,in This represents the deviation relative to the average microcrack length. Therefore, we have... (41) The average microcrack length and The variance of the microcrack length is denoted as .
[0029] It can be simplified to: (42) The total energy release rate can be obtained by superimposing the energy release rate associated with macrocracks with the additional energy release rate associated with microcracks. (43) 3. Total energy release rate Wear life prediction: Macroscopic crack energy release rate and the additional energy release rate of microcracks After superimposing the total effective energy release rate of the wear process, the wear life can be predicted based on the fatigue crack propagation characteristics of the material. Specifically, the wear life can be predicted by... Substitute the crack propagation rate formula for the material (e.g., the Paris fatigue crack propagation law): ,in and For material constants, The energy release rate amplitude exceeds the material fatigue threshold. The corresponding crack propagation rate is obtained from the first part. Then, based on the critical crack length criterion, the number of cycles required for the material to propagate from the initial crack to failure is calculated. This is the wear life of the material under this working condition. For a given initial crack length... Failure criterion: crack length The lifetime can be estimated using the formula for the spread rate of multi-cracks: (44) Through the above process, the present invention can predict the long-term wear life of materials based on short-term laboratory tests, which greatly improves the efficiency and scientific nature of life prediction.
[0030] Example 1: Taking the prediction of tire wear of a certain rubber material as an example, the above method will be explained. Assume the Young's modulus of this material is... Pa, Poisson's ratio Select equivalent pavement particle width ,length Based on the actual vehicle load and road conditions, the test tangential force was set to... N, vertical force N, assuming it's converted to the vertical force per sandpaper grain. tangential force Substituting the above parameters into the formula, we can obtain the macroscopic crack energy release rate. about Let's assume the additional energy release rate of the microcrack. about Therefore, the total energy release rate .
[0031] Based on the fatigue crack propagation characteristics of this rubber material as previously determined, its fatigue threshold energy release rate is assumed. Crack propagation beyond the threshold follows the Paris rule: Assuming an empirical constant is taken and .Will Substituting the values, the fatigue crack propagation rate is approximately The loop, assuming the material initially has a length The crack, when the crack extends to The number of loops required for the (failure criterion) can be estimated as follows: (45) In other words, under the above load and operating conditions, approximately after After several loading cycles, critical-sized cracks will appear on the material surface, leading to significant wear failure. To further verify the effectiveness of the wear prediction method and testing equipment, wear tests and predictions were conducted on materials with different Young's moduli and different normal pressures. Figure 3 As shown, by keeping the test conditions constant, such as loading conditions and abrasive sandpaper constant, and conducting wear tests with materials of different Young's moduli (these materials are artificially synthesized through proportioning), the predicted results and test results show a high degree of agreement. Figure 4 As shown, by keeping the test materials constant, such as the material being worn and the abrasive sandpaper constant, and changing the loading conditions to vary the vertical force per particle, the predicted results and the experimental results still show a high degree of agreement. This demonstrates that the prediction method and test apparatus are effective and robust under different materials and loading conditions.
[0032] Example 2: Applying the above conditions to a material with higher rigidity (e.g., steel) verifies the applicability of the method of the present invention to different materials. Assuming the Young's modulus of the material... Pa, Poisson's ratio Maintain the same geometric parameters and load conditions as in Example 1. , , N, N), the macroscopic crack energy release rate was calculated. Approximately Additional energy release rate of microcracks Approximately Therefore, the total energy release rate This is far below the fatigue crack propagation threshold energy release rate of typical steel. In other words, the energy release rate generated by the steel at this load level is insufficient to drive crack propagation, and the material will hardly experience fatigue wear. Therefore, according to the method of this invention, the wear life of steel under this condition is predicted to be very long (theoretically approaching infinity), consistent with the excellent wear resistance of steel rails, steel wheels, etc. in practice. This embodiment illustrates that the method of this invention can provide reasonable wear life predictions based on the mechanical properties of different materials: for soft, low-stiffness materials (such as rubber), fatigue cracks are easily generated and wear occurs under a certain load, while for high-stiffness materials (such as steel), fatigue damage may hardly occur under the same load, resulting in extremely slow wear.
[0033] Parameter Influence Analysis: The model of this invention can also be used to analyze the influence of various factors on energy release rate and wear behavior. For example, under other fixed conditions: Increasing the Young's modulus of the material It will significantly reduce the total energy release rate. and additional energy release rate The more rigid the material, the less likely it is to experience wear fatigue under the same load.
[0034] Increase the vertical force per particle or tangential force Both increase the energy release rate, but their effects on the additional energy release rate differ. Increasing the vertical force per particle... This will significantly increase the additional energy release rate of microcracks, and increase the tangential force per particle. right The impact is relatively small. Therefore, under high vertical load conditions, microscopic fatigue damage will be more severe. The above pattern is consistent with the calculation results of the theoretical model of this invention and existing experimental observations, which indirectly verifies the rationality of the model.
[0035] Key points of implementation: It should be noted that when using this invention to predict wear life, it is necessary to obtain some mechanical parameters of the material in advance: (1) Material fatigue crack propagation characteristic parameters, such as the coefficient C, exponent m and fatigue threshold energy release rate in the Paris formula. E.g., can be determined through standard material fatigue crack propagation tests.
[0036] This method first converts vehicle load and road surface roughness into test parameters based on actual working conditions, including tangential force, vertical force, equivalent road particle width and length, and stepper motor speed. Then, a rapid wear test is conducted on a matching wear testing device. A loading head with sandpaper is applied to press the test material under a set load, and a rotating wheel covering the test material is driven by a stepper motor to simulate actual wear. During the test, the device measures and records the tangential and vertical forces in real time, collects the wear particles, and measures their particle size distribution to obtain the average particle size and particle size variance of the wear debris. Based on the linear elastic fracture mechanics theory, the total effective energy release rate under the combined action of macro and micro cracks is calculated, and the fatigue crack propagation rate of the material is obtained accordingly. Combined with the critical crack length of the material, the wear life is predicted. The testing device has a simple structure and low cost, and can complete a wear prediction test in about 5 minutes, significantly shortening the testing cycle. This method is based on a macroscopic and microscopic fatigue fracture mechanics model of the material, has a solid theoretical foundation, a wide range of applications, and considers the particle size distribution of wear particles in the calculation, making the prediction results more scientific and accurate.
[0037] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art will be able to make various modifications and improvements without departing from the principles of the present invention, and these modifications and improvements should also be considered to fall within the scope of protection of the present invention.
Claims
1. A wear testing device based on the macro- and micro-scale fatigue fracture mechanics of materials, characterized in that, include: A base plate (1) and a guide rail frame (2) mounted on the base plate (1); the guide rail frame (2) is provided with a vertical guide rail (3) and a slider (4) that slides up and down along the guide rail (3); a cantilever support (6) is fixed on the slider (4), a loading device frame (5) is mounted on the cantilever support (6), and a loading and mechanical measurement assembly device (7) is assembled on the loading device frame (5), the front end of the loading and mechanical measurement assembly device (7) is provided with a loading head (8), and the surface of the loading head (8) is covered with test sandpaper; a stepper motor mounting frame (14) is fixedly mounted on the base plate (1) through a support (15), and a stepper motor is mounted on the stepper motor mounting frame (14). (13) The output shaft of the stepper motor (13) drives the rotating wheel (10) to rotate through the pin connection. The outer peripheral surface of the rotating wheel (10) is covered with the test wear material sample (9). The loading head (8) can press against the surface of the test material (9) on the rotating wheel (10) in the vertical direction with the vertical force. The rotation direction of the rotating wheel (10) is parallel to the plane of the base plate (1). The test device is provided with a particle isolation cover (16) to close the wear test area. The particle isolation cover (16) is provided with a test hole (11). The probe of the particle test device (12) extends into the particle isolation cover (16) through the test hole (11) to collect wear particles.
2. The wear testing device based on macro- and micro-scale fatigue fracture mechanics of materials according to claim 1, characterized in that, The type of sandpaper used on the loading head (8) is selected based on the roughness parameters of the actual road surface.
3. The wear testing device based on the macro- and micro-scale fatigue fracture mechanics of materials according to claim 1, characterized in that, The speed of the stepper motor (13) is set to correspond to the simulated actual vehicle speed.
4. The wear testing device based on the macro- and micro-scale fatigue fracture mechanics of materials according to claim 1, characterized in that, The loading and mechanical measurement assembly (7) integrates a force sensor, which can measure the tangential force and vertical force experienced by the loading head (8) during the friction process, and transmit the data to the data recording system.
5. The wear testing device based on macro- and micro-scale fatigue fracture mechanics of materials according to claim 1, characterized in that, The particle testing device (12) is a particle size analyzer.
6. A wear prediction method based on the macro- and micro-scale fatigue fracture mechanics of materials, characterized in that, The method is implemented based on the testing apparatus of claim 1, and includes the following steps: Step 1: Select test parameters based on actual working conditions, and convert the actual working load into the required tangential force per particle for the test. and vertical force The width of road surface particles is calculated based on the road surface unevenness and roughness. With particle length Select with the and Sandpaper with a corresponding roughness is used as the abrasive medium, and the rotational speed of the stepper motor (13) is set to the equivalent value of the vehicle's driving speed; Step 2: Conduct the wear test according to the selected test parameters. Fix the wear material sample (9) to the outer surface of the rotating wheel (10), cover the selected sandpaper on the loading head (8) of the loading and mechanical measurement assembly device (7), and set the vertical load. Under the action, the loading head (8) is pressed against the surface of the test material (9); The stepper motor (13) is started to drive the rotating wheel (10) to rotate at the equivalent vehicle speed, so that the sandpaper on the loading head (8) and the surface of the test material (9) will undergo relative friction to generate wear; the particle test device (12) is inserted into the test hole (11) of the particle isolation cover (16) through the particle test hole (11) to collect the particles generated by wear and measure the particle size distribution, so as to obtain the average particle size and particle size variance of the wear particles; Step 3: Calculate the total energy release rate according to the following formula. : Among them, under plane stress conditions Under plane strain conditions Poisson's ratio of the material; For the width of road surface particles, For the length of road surface particles, The Young's modulus of the test material. The equivalent Young's modulus of the cracked material; For the tangential force per particle, The vertical force per particle; The length of the macroscopic crack; Microcrack density; The average particle size of the wear particles. The variance of wear particle size; Step 4: Based on the calculated total energy release rate Find the fatigue crack propagation rate for the corresponding material; Step 5: Estimate the wear life of the material based on the fatigue crack propagation rate and the critical crack length of the material.
7. The wear prediction method based on macro- and micro-scale fatigue fracture mechanics of materials according to claim 6, characterized in that, Step 4 further involves: calculating the... Substitute the fatigue crack propagation characteristic curve of the material into the curve to determine the corresponding fatigue crack propagation rate. The crack propagation characteristics are obtained through prior material fatigue tests.
8. The wear prediction method based on macro- and micro-scale fatigue fracture mechanics of materials according to claim 6, characterized in that, The type of sandpaper used on the loading head (8) is selected based on the roughness parameters of the actual road surface.