Preparation of Composite Lubrication Structure and its Tribological Properties on 45^# Steel Surface

The composite lubrication structures were prepared by incorporation of solid lubricant into micro-dimples produced by laser surface texturing on the surface of 45^# steel. The tribological properties of solid lubricant films on textured surfaces were compared with the behavior of burnished solid lubricant films on ground surfaces. The effects of the density and the diameter of the dimple reservoirs on the tribological properties were investigated. The wear tracks of the samples were observed using scanning electronic microscopy (SEM) and energy dispersive spectrometer (EDS). The results show that a significant decrease in friction and wear was achieved for the textured surfaces compared to that of untextured surfaces. It is shown that the friction coefficient reduced with increasing dimple density for the same dimple diameter. Optimum density (20%～35%) of the dimples was revealed. When the dimples density was less than 20%, the friction coefficient was lower for the textured surface with small dimple diameter. However, the friction coefficients increased with CM(49reducing of dimple diameter when the dimples density is more than 35%. The analysis of samples surfaces showed that low friction and long wear lifetime of burnished film on LST steel surfaces was apparently provided by preservation of thin MoS₂ film around the dimples and by supply of solid lubricant from the dimples to the surface.