Tribological Properties of Muscovite, CeO2 and Their Composite Particles as Lubricant Additives

CeO2 nanoparticles and muscovite/CeO2 (abbreviate: MC-Ce) composite particles were prepared by mechanical solid-state-chemistry-reaction method followed by surface modification with oleic acid. The microstructure of the materials was characterized by XRD, SEM, EDS and FTIR. The tribological properties of muscovite, CeO2 and MC-Ce dispersed into lubricant grease were investigated, and the worn surface was analyzed by SEM, EDS and XPS. Results show that muscovite, CeO2 and MC-Ce all can improve the friction-reduction and antiwear properties of lubricant grease and MC-Ce composite particles present better tribological performance than single particles. The excellent tribological performance of MC-Ce can be attributed to the formation of a chemical reaction film mainly consisting Fe2O3 and SiO2 as well as the formation of an adsorption film of MC-Ce on the worn surfaces.