Effects of CeO2 on the microstructure and tribological properties of atmospheric plasma-sprayed Cr2O3-TiO2 coatings

Purpose The purpose of this paper is to study the mechanism and effect of rare earth oxides on the properties of Cr2O3-TiO2 coating. Design/methodology/approach Cr2O3-TiO2 coatings with different proportion of CeO2 were deposited by atmospheric plasma spraying on aluminum alloy 7005. The mechanical, microstructure and tribological properties were studied. Findings The addition of CeO2 could improve the micro-hardness; decrease porosity, wear rate and surface roughness of the coating; and increase the bonding strength between the coating and substrate. The wear mechanism is a mixture of abrasive and adhesive wear. Originality/value The addition of CeO2 could refine microstructure, and promote the formation of solid solution structure, and then affect the properties of coatings.