Tribology Behaviors of LaF3 Nano Particles in 500SN Base Oil

LaF3nanoparticles were used as an additive to improve tribological performance of base oil stock. Their surface modifiers were prepared by a precipitation method, using two kinds of salts from dioctyl-dithiophosphoric acid and piperidine or di-(β-ethoxyl) stearamine. Morphology and structure of LaF3nanoparticles were investigated. The tribological behaviors of these solid-containing lubricating oils were measured by using a conventional four-ball machine. Wear scar surfaces on the test steel balls were examined by instrumental analysis to elucidate the anti-wear mechanism.