Improvement of erosion performance of WOKA HVOF coating reinforced by ceramics and carbide powdered materials: A case study

This study presents the testing of the effectiveness of various additives in WOKA 3533 (WC-10Co4Cr) cermet HVOF coating while it was being eroded by sand slurry. WOKA cermet powder has additions of molybdenum carbide, yttrium oxide, and zirconium oxide, all at the same concentration of 3 weight percent. The additive-based WOKA cermet coatings were developed via high-velocity oxy-fuel (HVOF) spraying. The pot tester was used to examine the effects of slurry erosion in ashy conditions. In addition to analyzing the microstructure and crystalline phases of as-sprayed coatings and microhardness, this research also compared the mechanical characteristics of conventional and additive-based WOKA cermet coatings. Examining the results, one can see how various cermet coatings do in terms of surface erosion and wear. Yttrium oxide was identified as a superior addition to molybdenum carbide for use in WOKA cermet coatings. Zirconium oxide, however, is not a good fit for WOKA cermet coatings in erosion wear environments.