Friction And Wear Characteristics Of Coated Surface With Mesostructure Based On Thermal-Mechanical-Wear Coupling

There is a problem of sliding friction and wear on the contact surface of automobile brake disc during braking.The contact surface will be worn by the accumulation of friction heat and long-term cyclic load,which will seriously affect the actual service life of the brake disc.How to improve the friction and wear performance of contact surface is of great significance to improve the efficiency and life of brake disc and most mechanical equipment.In this paper,taking the friction disk as the research object,the phenomenon and law of friction and wear on the coated surface of the friction disk are studied by using the heat-force-wear coupling analysis method.The main research contents and results are as follows:(1)Study on geometric model establishment and wear numerical analysis method of friction disk on coated surface.The friction disk on the deposited coating surface is prepared,the point cloud data of the initial topography of the coating surface are extracted,and the geometric model of the friction disk on the real coating surface is established by using the reverse modeling method.The pin-disk friction and wear test were used to explore the evolution of the radial morphology of the coated surface of the friction disk at different times.Based on the discretization of Archard wear model,combined with the evolution law of friction disk morphology,a cumulative jump analysis method of wear morphology is proposed,which is convenient to analyze the dynamic evolution of wear morphology of coated surface for a long time.(2)Study on friction and wear characteristics of friction disk on coated surface.Based on the geometric model of the friction disk on the real coated surface and the actual working condition parameters of the pin disk test,the finite element simulation model of the friction disk on the coated surface is established,and the wear simulation algorithm is developed based on the cumulative jump analysis method of wear topography.Combined with the thermal-mechanical-wear complete coupling analysis method,the coupling problems of the three physical fields are solved,and the changes of wear morphology,temperature field and stress field distribution of the coated surface are studied.The effect of working condition parameters on surface friction and wear properties is studied,and it is found that the wear depth of coated surface is reduced by 29% under the same working conditions.(3)Study on the effect of micro-structure of coated surface on the friction and wear characteristics of contact surface.The friction disk models of different coating types of meso-structure are designed,and the effects of angle,spacing and quantity of micro-structure of coating type on wear morphology,temperature field and stress field are analyzed.The coating meso-structure can significantly improve the friction and wear properties of the contact surface.When the coating angle is 75 °,the distance between 0.75 mm and the amount is 36,the wear morphology is more uniform,and the wear depth,temperature and stress are the lowest.(4)Optimal design of micro-structure parameters of coating type.Based on the response surface optimization method,the 3D response is established to optimize the geometric parameters of the coating meso-structure.The friction disk on the coated surface is processed according to the optimized parameters,and the friction and wear tests are carried out to verify the validity of the prediction results.The results show that the geometric parameters of the micro-structure of the coated surface can improve the friction and wear properties of the surface,and the wear degree of the structure surface decreases significantly after optimization,and the wear degree of the test is close to the predicted value.In this paper,the effect of coating technology on the surface friction and wear performance of friction disk is studied,the influence of working condition parameters on surface wear morphology,temperature field and stress field distribution is explored,and the friction disk model with different coating meso-structure is designed.the effects of different structural parameters on surface friction and wear properties are analyzed.It provides a theoretical basis for improving the friction and wear performance of dry sliding friction contact surface,and provides technical support for improving the working efficiency and service life of mechanical equipment.