Tribological study of a thin TiO2 nanolayer coating on 316L steel

In the present study, the properties of thin coatings deposited on biocompatible 316L steel to improve the wear resistance were investigated. A thin Ti nanolayer of thickness 400 nm was deposited by thermal evaporation (sputtering), and the Ti-coated steel was subjected to plasma oxidation treatment for different times. All the samples were characterized using metallographic techniques, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), atomic force microscopy (AFM), and roughness and nanohardness tests. A pin-on-disc tribometer was used to evaluate the wear resistance of the coatings under lubricated sliding condition. The results showed that the TiO2 film is formed as a function of thermal oxidation time. The coating had a beneficial effect on the wear resistance depending on the roughness. Other coating characteristics such as topology of surface modified by TiO2 diffusion and nanohardness were assessed.