Superstoichiometric PVD carbide coatings

In recent years a number of developments have been made in the field of hydrogendashcontaining carbon coatings. These coatings are well known because of their low friction coefficient, e.g. against steel, they have many applications such as friction and wear-reduced coatings for machine parts. These coatings can be deposited by PVD methods. A stabilization 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 vapourized in a carbon and hydrogen atmosphere. Many workers have studied the carbondashrich side of the system for low friction applications, but superstoichiometric films in the range of about 50–60 at.% carbon also show interesting properties. The investigated systems are SiC, TaC and TiC. s paper the mechanical properties (hardness, critical load), microstructure (XRD, SEM) and the tribological properties (PindashOndashDisk Test) of these carbide coatings will be presented and discussed.