A comparative study on the tribological behavior of ID-HVOF sprayed Inconel 625 coatings under different temperatures

Inconel 625 is a nickel-based superalloy widely applied to industrial components to protect surfaces from high-temperature oxidation, wear, and corrosion. This enhances product lifespan, reduces downtime, minimizes maintenance costs, and lowers environmental impact. Internal Diameter High-Velocity Oxygen Fuel (ID-HVOF) is a novel thermal spray technique for application of coatings to inner surfaces of components. It can produce coatings with high density, low porosity, and excellent adhesion. This study investigates the temperature-dependent tribological properties of ID-HVOF-sprayed IN625 coatings, focusing on wear rate, friction coefficient, and wear mechanisms under controlled temperatures simulating room, intermediate, and high operational conditions. Investigations into the microstructural properties of the coating, using scanning electron microscopy (SEM) and Energy-Dispersive X-ray Spectroscopy (EDS) were performed. Wear tests were conducted using a pin-on-plate reciprocating sliding geometry at room temperature, 300°C and 800°C. The counterpart was aluminum oxide spheres with 6 mm in diameter under a normal load of 5 N, at 1 Hz with a constant sliding distance of 100 meters. Analysis of the worn surface and the counterpart was performed to investigate the friction response and wear mechanisms. This included examining the morphology of the wear track, chemistry and mechanical properties of the third bodies.