Effect Of Surface Topography And Performance Control Of Rolling Bearing Contact Interface

Rolling element bearing is a kind of rotating support component,which is widely used in engineering machinery,transportation,aerospace,precision instruments and other fields.With the improvement of industrial technology and manufacturing level,people put forward higher requirements for the stability and reliability of rolling bearings.Because the rolling bearing is often in the state of Elastohydrodynamic Lubrication in the process of operation,under this lubrication condition,the raceway surface topography plays an important role in the operation and life of rolling bearing.The influence of raceway surface topography effect on the friction and lubrication characteristics of contact interface is studied,and the basic research on lubrication mechanics,fatigue life prediction and friction and wear analysis of rolling bearing is carried out.The research work not only has important theoretical significance,but also has practical engineering application value for improving the quality of bearing design and manufacturing,and improving the reliability,safety and stability of mechanical system.In order to improve the tribological properties and basic fatigue life of rolling bearings,the mechanical analysis,three-dimensional characterization of surface topography,interface lubrication analysis,friction and wear analysis and contact fatigue life analysis of rolling bearings are carried out in this dissertation,which provides theoretical basis for the design,manufacture and performance control of rolling bearings.The main research work and contributions of this dissertation are as follows:（1）Based on the mechanical analysis theory of rolling bearing and the thermal network method,the quasi-static equation and the steady-state temperature field model of bearing are established.The variation laws of internal and external contact angle,contact load and temperature rise of angular contact ball bearing under different working conditions are studied,and the simulation results are verified by the temperature rise test of rolling bearing.The results show that the contact angle and contact load between the rolling element and the ferrule are very different under different loads and speeds;The steel ball/raceway friction pair is not only the main source of bearing heat generation,but also the position with the highest bearing working temperature.Improving the lubrication performance of the friction pair plays a positive role in reducing the bearing temperature rise and improving the bearing performance.（2）Some parameters in ISO 25178 three-dimensional topography characterization parameter system were selected to quantitatively characterize different surface textures.The relationship between characterization parameters and surface tribological properties was studied by point contact reciprocating friction test.Using YLP-F10 fiber laser marking machine,a set of surface texture is designed and manufactured on the contact surface of joint bearing.The friction experiment is carried out on the self-developed aviation joint bearing experimental machine,and the influence of surface texture on the friction coefficient and temperature rise of joint bearing is studied.（3）On the basis of mechanical analysis,combined with the theory of elastohydrodynamic lubrication and the method of elastic deformation based on surface topography spectrum analysis（amplitude reduction）,the elastic deformation analysis method of point contact elastohydrodynamic interface surface topography is studied,and the elastic deformation results of point contact elastohydrodynamic interface under different working conditions are calculated by using this method.The influence of elastic deformation of surface topography on the characteristics of contact interface and lubrication characteristics is discussed through the characteristic analysis of three-dimensional surface topography parameters before and after elastic deformation.The results show that significant elastic deformation occurs after the simulated gaussian surface and the measured textured surface enter the elastohydrodynamic contact area,and the elastic deformation changes dynamically with the change of working conditions.The elastic deformation flattens the surface micro convex body,and the variation laws of three-dimensional topography characterization parameters are different.The results provide a theoretical basis for further analyzing the influence of dynamic changes of surface topography on tribological properties.（4）The amplitude reduction method is combined with the numerical solution of Reynolds equation of elastohydrodynamic lubrication to study the simulation method of fast solving elastohydrodynamic lubrication of rough surface.By using this method,the variation characteristics of surface topography and the corresponding oil film thickness and pressure distribution of point contact elastohydrodynamic contact area under different working conditions are calculated,and the variation of surface topography parameters is related to the maximum oil film pressure and minimum oil film thickness.The influence of the dynamic change of surface topography on the bearing and lubrication characteristics of the bearing was analyzed.The results show that the maximum contact pressure increases and the minimum oil film thickness decreases due to the change of surface topography.The real film thickness ratio considering the dynamic change of surface topography intersects the nominal film thickness ratio calculated by the traditional method,which can better reflect the actual lubrication state of the contact interface.Increasing the change rate of surface S_al is conducive to improving the surface lubrication characteristics.（5）According to the results of lubrication analysis,based on the theory of subsurface stress and bearing contact fatigue life model,the prediction model of subsurface stress and life of EHL was established.The distribution of subsurface stress and rolling contact fatigue life of EHL under different working conditions were calculated by using the model,and the variation of topography parameters was correlated with the subsurface stress and life.The influence of the dynamic change of the surface topography of the elastohydrodynamic contact zone on the subsurface stress and fatigue life of the bearing was investigated.The results show that the surface topography has a significant effect on the subsurface stress field of the EHL contact interface.The maximum pressure of the EHL oil film is linearly related to the maximum stress of the subsurface.The appropriate surface texture can effectively improve the bearing fatigue life.Under high-speed working conditions,reducing the surface S_ku are beneficial to improve the contact fatigue life.In this paper,the dynamic change characteristics of the surface topography of the EHL contact interface are characterized and described theoretically,and the significance of the dynamic change characteristics of the surface topography for predicting and controlling the surface functional characteristics is revealed.The feasibility and effectiveness of the application of the active design of the surface topography in the regulation of the tribological performance of the rolling bearing are confirmed by simulation and experiment.The research results provide a theoretical basis for the surface topography design of rolling bearing and a new idea for the performance optimization of rolling bearing.