Tribological and Friction-Induced Vibration Behaviors of Inorganic Fullerene-Like Tungsten Disulfide and Three-Dimensional Graphene as Lubricant Additives

Friction and friction-induced vibration have a great impact on the service life of mechanical systems. In this study, the tribological performances and vibration characteristics of three-dimensional graphene nanosheets (3D GNS), inorganic fullerene-like tungsten disulfide (IF-WS₂), and their mixed additive lubricants are investigated by experiments. The results show that IF-WS₂/3D GNS (1:1) mixed additive can improve the friction-reduction and anti-wear of base oil by 62.9% and 71.4%, respectively. In terms of vibration damping, the mixed additive has an extremely strong dampening effect on vibration acceleration in all directions, especially in the Z-axis direction, where the amplitude is reduced by about 90%. The vibration damping should be attributed to the filling effect of 3D GNS and IF-WS₂, which greatly flattens the friction surface, thus reducing the number of collision micro-bumps in the relative movement of the friction pair and suppressing the vibration. In addition, the unique ductile deformation of IF-WS₂ makes the two additives form a flexible ball-bearing damper between the two contact surfaces, thus greatly reducing the vibration.