Influence of oxidized ceramics on the tribological properties of Ni60/WC composite coatings

Abstract

Ni-based composite ceramic coatings with good comprehensive performance are obtained by a supersonic plasma spraying process. A ceramic powder is added to a Ni60/WC powder to make the surface of the sprayed sample more uniform and compact. Pores are present on the surface of the two composite ceramic coatings prepared by NiWT(Ni60/WC + TiO2) and NiWA(Ni60/WC + Al2O3), as well as five phase components. In the microscopic morphology of the two composite ceramic coatings, the surface composition of the NiWT coating is relatively uniform and the surface of NiWA exhibits a cluster structure with more pits than NiWT. The friction coefficient of the NiWT coating at 200 r min−1 is between 0.40 and 0.43 and that of the NiWA coating is between 0.35 and 0.38. Simultaneously, the abrasion width and wear volume of the NiWT and NiWA coatings are small compared with the substrate, while the abrasion width and volume of the NiWT coating are smaller. The composite ceramic coatings prepared by the addition of two kinds of oxidized ceramics, through comparative analysis of the experiment, showed that NiWT had an improved surface micro-morphology and wear resistance than NiWA. The wear morphology of NiWT showed a wear mechanism of abrasive particles and the wear morphology of NiWA showed a fatigue wear mechanism.