Low Friction and Wear of a-C:H Films by Lubrication of 3D Graphene/Hexagonal Boron Nitride Composite in Atmospheric Environment

The hydrogenated amorphous carbon (a-C:H) film, which is widely used in the engineering field, has attracted more and more researchers' attention. A-C:H films exhibit super-low friction coefficient and low wear in inert atmospheres but high friction coefficient and wear in ambient air. In this study, 3D graphene and h-BN were used as solid lubricants to reduce the friction and wear of steel-a-C:H film contact conditions under different loads. When 0.01 wt% of 3D graphene and 0.1 wt% h-BN were mixed at a volume ratio of 1:1, the lubricating effect is optimum. Compared with a-C:H films, not only the friction coefficient is reduced, but also the wear rate is further reduced. This is mainly due to the formation of an ordered and dense transfer film on the sliding interface, which effectively prevents the direct contact between the surfaces of the friction pair.