Study on the Tribological Mechanism of Ultrafine SiO<sub>2</sub>/MoS<sub>2</sub> Powders in Complex Calcium Sulfonate Grease

The purpose of this work was to study and further clarify the anti-wear and anti-friction mechanism of ultrafine SiO 2 /MoS 2 powders in the complex calcium sulfonate grease. In this paper, 15nm nanoSiO 2 , 1μm MoS 2 and commercial NLGI Grade No.2 complex calcium sulfonate grease were used as the research objects, SEM, EDS and XPS were used to study the morphology, composition and film chemical constitution of the long friction wear spots of grease containing single nanoSiO 2 powder, ultrafine MoS 2 powder and the two compound powders, which formed in the process of four ball long friction. The results show that nanoSiO the grease plays a role in filling the undercut, ball bearings and polishing and forming high hardness Ca 3 Fe 2 (SiO 4 ) 3 and part of Fe 2 O 3 anti-wear films in the process of long friction. The ultrafine MoS 2 powder has a self-repairing effect to fill the grooves,forming the MoS 2 , MoO 3 anti-friction films and Fe 2 (SO 4 ) 3 anti-wear film. The two powders in the composite grease have a synergistic effect, acting on the friction pair together, and simultaneously forming self-repairing anti-friction and anti-wear films, thereby further improving the tribological performance of the base grease.