Preparation and tribological behaviors of magnesium silicate hydroxide-MoS2 nanoparticles as lubricant additive

The tribological properties of lubricating oil during service life largely depend on the properties of lubricant additives. Herein, we present a hydrothermal synthesis of magnesium silicate hydroxide (MSH)-MoS2 nanocomposite and evaluate its tribological performances and repairing properties on worn surfaces as lubricant additive in poly-alpha-olefin (PAO). The microstructure of MSH-MoS2 powders is MSH nanotubes surrounded by layered MoS2. The tribological test results show that the anti-friction performance and wear resistance of the friction pair were improved by 27.7% and 37.4%, respectively, after adding 1.0 wt% MSH-MoS2 into PAO. More importantly, the worn volume of the friction disk can be repaired by 33.2% after sliding 5 h under the lubrication of PAO with MSH-MoS2. The superior tribological performance should be attributed to the formation of robust tribofilm with low shear strength, high hardness, strong resistance to plastic deformation, and high bonding strength on the sliding surface.