Tribological Properties of Chromia and Chromia Composite Coatings Deposited by Plasma Spraying

Abstract

Cr2O3 and Cr2O3–SiO2-TiO2 coatings are deposited on P265GH steel using atmospheric plasma spraying. The influence of silicon oxide—titanium oxide addition on the surface morphology of the coatings, phase composition and tribological properties under non-lubricated sliding conditions are investigated. The addition of SiO2-TiO2 led to the formation of a more uniform surface morphology and reduce the surface roughness of the Cr2O3 coatings. The X-ray diffraction (XRD) studies indicated that both coatings are composed of an eskoloite Cr2O3 phase. The friction coefficients of the Cr2O3 coating are 0.504 and 0.431 when 1 N and 3 N loads were used, respectively. Meanwhile, the Cr2O3–SiO2-TiO2 coating demonstrated slightly lower values of friction coefficients under similar loads. The specific wear rate of the as-sprayed coating is reduced with the addition of SiO2-TiO2. It was found that the wear rates of the Cr2O3 and Cr2O3–SiO2-TiO2 coatings are up to 20 times lower compared to the steel substrate. This article is an expanded version of the “19th international conference on plasma physics and applications” conference abstract.