Analysis of the lubrication process with composition of solid lubricants of laser-modified sliding surfaces

Solid lubricants have been applied diffusely in numerous domains. This article investigates the impacts of each component in composite solid lubricants on the tribological performance and compares the antifriction effects of different kinds of solid lubricants to solve the lubrication problem of sliding bearing. Surface textures with dimples were fabricated on the surfaces of GCr15 bearing steel by a Q-switched solid-state Nd:YAG laser. The composite solid lubricants were filled in the micro-dimples by the deposition processes of heat-maintaining and pressure-maintaining, consisting of blinding elements and lubricating elements. Tribological performances under sliding friction for different kinds of adhesives and lubricants with different grain sizes were evaluated by ring-on-disk tribometer. On this basis, an orthogonal experiment of four factors and three levels (3(4)) was designed to investigate the impacts of different components of the solid lubricants on the tribological performance. Solid lubricants with nanoparticles can enhance antifriction ability: the friction coefficient of nano-graphite is 18.9% lower than that of micron-graphite, and the friction coefficient of nano-sized molybdenum disulfide declines 7.6% comparing to that of micron-sized molybdenum disulfide. According to the results of the orthogonal experiment, the optimal formula of the composite solid lubricants was graphite:molybdenum disulfide:polyimide:carbon nano-tubes = 4:1:0.5:0.4.