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A combination technology of the solid lubricant and the laser surface texturing (LST) can significantly improve the tribological properties of friction pairs. The plate sample was textured by fiber laser and composite lubricant of polyimide (PI) and molybdenum disulfide (MoS 2 ) powders were filled in the microdimples. Sliding friction performances of micron-sized composite lubricant and nano-sized composite lubricant were investigated by ring-plate tribometer at temperatures ranging from room temperature (RT) to 400 C. On the one hand, the results of the micron-sized composite lubricant show that the friction coefficient of the textured surface filled with composite lubricant (TS) exhibits the lowest level and the highest stability compared to a textured surface without solid lubrication, smooth surface without lubrication, smooth surface burnished with a layer of composite solid lubricant. The better dimple density range is 35-46%. The friction coefficients of the sample surface filled with micron-composite solid lubricant with the texture density of 35% are maintained at a low level (about 0.1) at temperatures ranging from RT to 300 C. On the other hand, the results of the nano-sized composite lubricant show that these friction properties are better than those of MoS 2 -PI micron-sized composite. The friction coefficients of MoS 2 -PI-CNTs nano-sized composite solid lubricant are lower than those of the MoS 2 -PI composite lubricant at temperatures ranging from RT to 400 C. In addition, the possible mechanisms involving the synergetic effect of the surface texture and the solid lubricant are discussed in the present work.

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Experimental studies of friction and wear on textured surfaces filled with composite solid lubricant and lubricated with grease were conducted on a sliding plain bearing to enhance the working performance and lifetime under different conditions. Circular microdimples of different diameters were fabricated on GCr15 bearing steel specimens using the semiconductor sound and light pumped Nd:YAG laser machining equipment. Ring-on-ring tribological test configuration with GCr15 tribopairs under a combined non-Newtonian lubrication of grease and composite lubricant was performed. The results showed that the surface textures on specimen GCr15 bearing steel material filled composite solid lubricant and lubricated with grease (TLG), reduced the friction by 27%, 46%, and 75% of the grease only (TG), solid lubricant only (TL), and nonlubricated (T) specimens, respectively. The textured specimen with dimple diameter of 109 μm lowered the maximum coefficient of friction by 38% and enhanced the antiwear properties of GCr15 bearing steel material remarkably. This indicated that grease has great potential in promoting service life and working performance of sliding plain bearing when combined with composite solid lubricant in a laser-textured surface. It is therefore beneficial for applications in the machinery and automotive components industries in saving energy and reducing CO2 emission.