POSTDEPOSITION TREATMENTS OF HARD COATINGS .2. ION-BEAM TREATMENTS OF TIN AND RELATED COATINGS

This paper presents an overview of the current state of the art on the effects of ion implantation treatments using nitrogen, argon and carbon on the tribological and structural properties of TiNx films. Data obtained by the authors and by other groups are discussed. Where available, data from similar treatments of related coatings (TiC and ZrN) are also presented. Improvements in tribological properties, in particular wear and adhesion, appear to be a general feature of implanted TiN coatings, irrespective of species and implantation parameters. However, ultramicrohardness of implanted films increases or decreases under various conditions, indicating that a number of different mechanisms contribute to wear improvements under various implantation regimes. Another common feature of implanted films is the observation that the treatment causes changes in the colour of the films, which vary with implanted species and dose. These changes are attributed to changes in stoichiometry induced by the beam in the upper layers of the films, and to changes in the surface texture.