Study on Tribological Behavior of Zinc Phosphate Impregnated Graphite Under Oil Lubrication Condition

Abstract The tribological behavior of zinc phosphate impregnated graphite (ZPIG) against nickel-based superalloy (GH4169) in oil environment was investigated, and the lubrication and wear mechanism were also determined in this study. Tribological tests were run under different tribological conditions using a ring-on-disk device. The results showed that, under any load conditions, zinc phosphate impregnated graphite had the lowest coefficient of friction (COF) and wear-rate at 200 rpm. Under the identical rotating speed condition, the minimum coefficient of friction and wear-rate were obtained when the load was 500 N and 1000 N. The lubrication mechanism, which could be reflected by the transfer layer of friction counterpart, was related to the coefficient of friction, wear-rate, and oil temperature to affect contact characteristics of two solid surfaces and formation ability of liquid film. The wear mechanism of zinc phosphate impregnated graphite under oil lubrication conditions was dominated by abrasive wear and material removal was achieved through the fracture mechanism.