Wear energy approach for evaluation of tribological properties of Cr 2 O 3 -TiO 2 coating

In the present work, Cr 2 O 3 -TiO 2 ceramic coating was deposited by atmospheric plasma spray (APS) method. Tribological response of coating was thoroughly examined using two different sizes of SiC abrasives under four distinct loads. Coatings were characterized by Scanning Electron Microscopy, Energy Dispersive Spectroscopy, x-ray Diffraction, Raman spectroscopy and x-ray Photoelectron Spectroscopy. The coating experienced 31%–40% lower friction coefficient at coarser particle size whereas 1.4–1.6 times lower wear rates were obtained at finer particle size. Results were explained on the basis of adhesion-abrasion components of friction. Consequences of formation of a tribo-oxide film and its implications on specific energy for material removal along with wear mechanisms are also discussed. A modified wear energy parameter (WEP) is used and showed good correlation with experimentally measured wear rates and friction coefficient of the coating.