Study on optimisation of asymmetrical microtextures in sliding friction pairs for enhanced lubrication

This study proposes the asymmetrical microtextures added to the surface of the sliding-friction-pair and optimisation of the geometric parameters in asymmetrical microtextures to improve the lubrication efficiency and bearing capacity of the sliding-friction-pair. From the lubrication model of sliding-friction-pair using rectangular asymmetrical micro-structures established, the parameters of the depth and tilting bottom surface in each microtexture are optimised by the genetic algorithm. The result indicates that with the optimal asymmetrical micro-structures distributed by two different regions of the boss and pit region and with the boundary between these two regions to be a curve towards the central area in the direction of the oil film flow, both the hydrodynamic pressure (p) and bearing capacity (W) of the oil film are higher than symmetrical microtextures. In particular, the maximum p and W are strongly increased in comparison with symmetrical microtextures. Thus, the work efficiency of sliding-friction-pair is significantly improved.