Wear Behaviour of Conventional and Nano-structured Thin Films of Titanium Aluminium Nitride

The coatings of TiAlN were deposited on AISI-347 grade boiler steel substrate out of which two were thin nano coatings deposited at different temperatures of 500°C and 200°C and one conventional coating was deposited by plasma spraying. The as sprayed coatings were characterized with relative to coating thickness, microhardness, porosity and microstructure. The sliding wear behaviour of uncoated, PVD sprayed nanostructured thin TiAlN coatings were investigated according to ASTM standard G99-03 using pin on disk wear test rig. Cumulative wear volume loss and coefficient of friction, µ were calculated. The worn out samples were analysed with SEM/EDAX. Wear rates in terms of volumetric loss (mm³/g) for uncoated and coated alloys were compared. The nanostructured TiAlN coatings deposited at 500°C and 200°C has shown minimum wear rate Nanostructured TiAlN coatings were found to be successful in retaining surface contact with the substrate after the wear tests.