Effects of substrate temperature and carbon content on the structure and properties of (CrCuNbTiY)C multicomponent coatings

(CrCuNbTiY)C multi-component coatings were prepared by co-sputtering of Cr, Cu, Nb, Ti and Y targets in an Ar + CH4 reactive atmosphere. The films, with two different carbon contents (C/metal ratio of about 1.1 and 2.7, respectively) were analyzed in terms of elemental and phase compositions, crystalline structure, surface and cross-section morphologies, mechanical properties and tribological performance. The influence of the substrate temperature (from 80 °C to 650 °C) on the microstructure and properties of the coatings was examined. The residual stress presented minimum values for the temperature variation range from 300 °C to 500 °C, while the film hardness monotonously increased with substrate temperature. Friction and wear performance of the coatings generally improved with increased temperature. The carbon rich films exhibited finer microstructures and superior mechanical and tribological characteristics than the almost stoichiometric ones.