Tribological Behavior of WS2 Nanoparticles as Additives in Calcium Sulfonate Complex–Polyurea Grease

Abstract

In order to improve the tribological properties of calcium sulfonate complex–polyurea grease, WS2 nanoparticles were used as additives to prepare WS2 calcium sulfonate complex–polyurea grease. The tribological behavior of WS2 grease on the GCr15 surface was systematically studied. The results indicate that WS2 nanoparticles can significantly improve the extreme pressure performance of calcium sulfonate complex–polyurea grease. When the concentration of WS2 nanoparticles is 2 wt.%, the friction coefficient decreases by 14.94%, and the maximum nonseizure load PB increases by 31.41%. As the temperature increases, the friction coefficient and wear rate of WS2 grease first decrease and then increase. This is mainly attributed to the adsorption and frictional chemical reaction between WS2 nanoparticles and the matrix.