Influence Of Laser Compound Micro Modeling On Friction Performance Of Sliding Bearing

Sliding bearing,as an important bearing component of various machines,is a common material for bearing bush of sliding bearing.It is of great significance to improve its wear resistance and friction reduction performance and prolong its service life.In this paper,the aluminum tin based bearing alloy Al Sn20 Cu is taken as the research object,and the research method of combining theoretical research,numerical simulation and experimental research is used to improve the friction performance and service life of the material by laser ablation processing of reticular texture and composite micro molding of pits.The main work of this paper is as follows(1)Based on the COMSOL numerical simulation,the influence of different dimple micro modeling parameters on the circumferential oil film pressure distribution,the change of oil film pressure area and the bearing capacity of oil film surface in the stable stage of sliding bearing was studied.The results show that the lubricating oil film of sliding bearing has the best dynamic pressure effect and bearing performance when the parameters of the micro shape of the concave are set.When the circumferential oil film pressure increases,the area of high oil pressure area decreases,but the pressure value increases;With the increase of the total area of high oil pressure zone,transition oil pressure zone and low oil pressure zone,the bearing capacity of oil film increases.(2)Based on the experiment of laser ablation pit micro modeling,the effects of laser process parameters and micro modeling parameters on surface morphology,roughness and Vickers hardness were studied.The results show that the depth,diameter and depth diameter ratio of pits increase with the increase of laser power and ablation times.With the increase of spot diameter,the pit depth decreases,the diameter increases and the depth diameter ratio decreases.The surface roughness increases with the increase of laser power and ablation times,but the change of roughness is small with the increase of spot diameter.The Vickers hardness is higher than that of the matrix material.Based on the experiment of laser ablated reticulated texture,the influence of texture parameters on the wettability of materials was studied,and the best parameters of the surface wettability of reticulated texture were determined.(3)Based on the friction and wear experiments of laser ablated dimple micro modeling and composite micro modeling,the rotational speed conditions of different lubrication states were determined through pre experiments.The results show that the parameters of mesh texture with better friction reducing effect are consistent with those of contact angle experiment.When the micro molding parameters are pit spacing 1.4mm,pit dislocation 0.5 mm and pit diameter 0.6 mm(depth diameter ratio 0.637),the bearing capacity is strong,which is consistent with the trend of numerical simulation results,thus verifying the correctness of the numerical simulation results.