Behera, N.Sarmah, P.Chandramouli, T.V.Ramesh, M.R.2026-02-032025Tribology - Materials, Surfaces and Interfaces, 2025, 19, 2, pp. 97-11017515831https://doi.org/10.1177/17515831251332401https://idr.nitk.ac.in/handle/123456789/20244This study examines the effects of Mo on the high-temperature wear and friction behavior of HVOF-sprayed 70%WC-Co/25%Mo/5%C and 70%WC-CrC-Ni/30%Mo coatings on Superni-76. The ball-on-disc tribometer wear tests were conducted at different temperatures (300°C and 600°C) and loads (10 and 30?N) against counter body Al<inf>2</inf>O<inf>3</inf> ball. Microstructures and phase formation were investigated using SEM/EDS and XRD. The characterization of coating microhardness, surface roughness, and coating density was examined. The 70%WC-Co/25%Mo/5%C coating showed lower surface roughness and higher microhardness values than the 70%WC-CrC-Ni/30%Mo coating. The wear rate of the substrate increases with an increase in temperature, whereas 70%WC-Co/25%Mo/5%C and 70%WC-CrC-Ni/30%Mo coatings decrease with temperature from 300°C to 600°C. The coefficient of friction of substrate and coating decreases with increasing temperatures. The worn surfaces of 70%WC-Co/25%Mo/5%C and 70%WC-CrC-Ni/30%Mo coating contain oxide phases (WO<inf>3</inf>, Cr<inf>2</inf>O<inf>5</inf>) and lubrication phases (M<inf>0.2</inf>W<inf>0.8</inf>O<inf>3</inf>, CoMoO<inf>4,</inf> and MoO<inf>3</inf>) at 600°C. These oxide phases reduced the coating wear rate and coefficient of friction at 600°C. The 70%WC-Co/25%Mo/5%C coating showed improved resistance to wear and lower friction coefficient than the substrate and 70%WC-CrC-Ni/30%Mo coating. At temperatures of 300°C, the main abrasive wear mechanism changes to oxidative wear when the temperature reaches 600°C for both coatings. © The Author(s) 2025.AbrasionAbrasive coatingsFatigue testingInorganic coatingsMicrohardnessNickel coatingsSprayed coatingsThermal fatigueCoefficient of frictionsEffect of moFriction behaviourHigh temperature wear behaviorHighest temperatureHVOFMo coatingsOxide phasisTribological performanceWear and frictionSolid lubricants