Tribological Behavior and Wear Resistance of Plasma Spraying MoSi2 and MoSi2-SiC Coatings

MoSi₂ and MoSi₂ composites with 10, 20 and 30 vol.% SiC particles coatings were fabricated by atmospheric plasma spraying (APS) under inert conditions and the influence of SiC content on the tribological properties of coatings was investigated. Powders of monolithic MoSi₂ and MoSi₂–SiC composite prepared by mechanically activated reactive synthesis route. The wear tests were conducted on a pin on plate apparatus under reciprocating sliding conditions at 27 and 300 °C temperatures. The results demonstrated that the wear resistance of the MoSi₂ coatings containing 20 and 30 % vol. SiC was enhanced compared to MoSi₂ coating at ambient temperature, but at 300 °C MoSi₂-20% vol. SiC had the optimum tribological properties over other coatings. The four observed dominant types of wear mechanisms were adhesive, surface fatigue, microfracture and abrasive, respectively.