Effect of thickness and carbon content on tribological behaviour and mechanical properties of Ti-C:H coatings

Abstract

In this study Ti x% -C:H coatings are deposited with varying thicknesses and different ratios of x% titanium target “poisoning” on tungsten carbide (WC) substrate by Unbalanced Magnetron (UBM) sputtering process and Optical Emission Monitoring (OEM) control. According to our results, the coating microstructure, mechanical properties, Raman spectra, and wear resistance vary according to different x% levels. The films are tested against different counterbodies under dry and lubricated conditions by oscillation friction and wear tester (SRV). According to those results, films with 2.5 μm thickness and x=10% poisoning level tested against AISI 1045 steel under linear contact wear mode have excellent tribological properties. All of the Ti x% -C:H coatings sliding against 6061 Al counterbody produce severe adhesion damage between the contact surface. In addition, these coatings are inappropriate for high pressure point contact wear mode under dry and lubricated conditions.