Investigations of tribological performance of slewing bearing raceway with bionic textured composite surface under grease lubrication

To improve the insufficient lubrication of slewing bearing, this study investigates the tribological properties of 42CrMo bionic textured composite surface (BTCS) with different densities under MXenes-Ti3C2 lithium composite grease (MLCG). Inspired by the micro-texture characteristics of the clamshell, BTCS is composed of 42CrMo and Sn-Ag-Cu (SAC) alloy. The results indicate that the tribological performance of BTCS (ρ = 38%) is improved most significantly, the average friction coefficient (0.056) and wear rate (6.4 ×10−8 mm3N−1m−1) of the counterpart ball reach the minimum, and the worn surface is fine and smooth. This is mainly attributed to the synergistic self-repairing effect of MXenes-Ti3C2 and SAC on the worn surface. Furthermore, SAC particles act as submicron rolling bearings, transforming the friction form into rolling-sliding.