Structural, mechanical and tribological properties of WCTiN coatings produced by HiPIMS

Abstract

Wear can be decreased by applying protective multi-element thin films on the surface of mechanical components (e.g., cutting tools and brake discs). The current study examines how substrate polarisation voltage affects the structural-mechanical relationships of WTiCN thin films made using a combination of HiPIMS and DCMS reactive sputtering. A chemical and structural study of the coatings conducted using EDS and XRD reveals the development of a composite phase structure. Additionally, the microstructure and morphology of the coating, as revealed by SEM and AFM, shows that defect-free surfaces are possible to obtain. Then, sliding (scratch and pin-on-disk) and indentation (nano-indentation) tests are used to examine the films’ mechanical characteristics (hardness, adhesion, friction coefficient and wear rate). It shows that substrate polarisation voltage of −60 V must be used to generate surfaces that are resistant to wear. The reason for this is the ideal levels of tungsten concentration (19 at.%), root mean square surface roughness (4.5 nm) and hardness (29 GPa) have been reached.