Evaluation of mechanical properties and tribological behavior of DLC/WC/WCN/W multilayer coatings deposited by HiPIMS

Abstract

In the present research, thin films of diamond-like carbon (DLC), tungsten carbide (WC), tungsten carbonitride (WCN) and tungsten (W) were deposited onto the surface of an AISI 52100 steel using the PVD process by HiPIMS. A (DLC/WC/W), B (DLC/WCN/W) and C (DLC/WC/WCN/W) coating systems were evaluated through mechanical and tribological tests to establish the optimal system for its application in the bearing industry. The physicochemical characterization was carried out using SEM and EDS. On the other hand, the mechanical properties were obtained by Berkovich instrumented indentation tests, where it was observed that the synergy between the WC/WCN intermediate bilayer in Coating C increased the hardness and elastic modulus concerning the WC and WCN intermediate monolayers. Finally, the coating systems were evaluated through the linear reciprocating wear test. Coating C presented the highest wear resistance and the lowest values of coefficient of friction, due to the positive synergy between the WC/WCN intermediate bilayer.