Microstructural insights and temperature effects on wear resistance of CuNiIn coatings: Comparison of HVOF and HVAF processes

Abstract

Cu-based coatings are ideal for protecting aerospace and industrial components from wear and failure. Traditionally applied using high-temperature methods like Atmospheric Plasma Spraying (APS) and High-Velocity Oxy-Fuel (HVOF), these techniques often increase oxygen content in coatings. Low-temperature processes, such as High-Velocity Air-Fuel (HVAF), reduce oxygen content, costs, and energy use while maintaining performance. This study investigates CuNiIn coatings deposited via Internal Diameter High-Velocity Air-Fuel (ID-HVAF) and HVOF. Both processes produced dense coatings with minimal oxidation. Friction increased from ∼0.49 at 25°C to ∼0.7 at 450°C, with minimal wear at 25°C and significant wear at 450°C. Ex-situ analysis revealed copper oxides glaze at 25°C reduced friction, while abrasive grooves dominated wear at 450°C.