SUPERSTOICHIOMETRIC PVD CARBIDE COATINGS

In recent years a number of developments have been made in the field o f hydrogen-containing carbon coatings. These coatings are well known b ecause of their low friction coefficient, e.g. against steel, they hav e many applications such as friction and wear-reduced coatings for mac hine parts. These coatings can be deposited by PVD methods. A stabiliz ation of these PVD-processes is possible if a metal component is added to the process. In this case a metallic target, e.g. titanium, is vap ourized in a carbon and hydrogen atmosphere. Many workers have studied the carbon-rich side of the system for low friction applications, but superstoichiometric films in the rang of about 50-60 at. % carbon als o show interesting properties. The investigated systems are Si-C, Ta-C and Ti-C.In this paper the mechanical properties (hardness, critical load), microstructure (XRD, SEM) and the tribological properties (Pin- On-Disk Test) of these carbide coatings will be presented and discusse d.