High-temperature erosion and sliding wear of thermal sprayed WC–Cr3C2–Ni coatings

Abstract

ABSTRACT The present work focuses on high-temperature solid particle erosion and sliding wear behaviours of WC–Cr3C2–Ni coatings deposited by atmospheric plasma spray (APS) and high-velocity oxy-fuel (HVOF) processes. The high-temperature erosion behaviour and the effects of temperature on the sliding wear performance of coated specimens were comparatively studied using an air-jet erosion tester and a ball-on-disc tribometer, respectively. Unidirectional dry sliding wear has been tested up to 800 °C, whereas the erosion tests were up to 650 °C. Interestingly, in a high-temperature sliding, the wear rates of both the coatings decreased after 500 °C due to the development of tribofilm. Furthermore, erosion resistance of both coatings was observed to be more prominent at 650 °C. HVOF coating offers higher erosion resistance than APS coating due to higher hardness, lower splat cohesion, lesser degree of decarburisation, and retained oxide layer. The HVOF-deposited WC–Cr3C2–Ni coating improves the high-temperature sliding wear and solid particle erosion resistance of the base material appreciably.