The effects of metal ion post-implantation on the near surface properties of TiN deposited by CVD

In contrast to the effect of non-metal ion implantation where changes in properties are related to the chemical and tribological character of the implanted zone, metal ion implantation hardens the substrate and enhances wear resistance to depths well beyond that zone. In the present work the surface properties of TiN deposited by chemical vapor deposition (CVD) and subjected to a metal ion implantation post-treatment: surface topography, frictional properties and residual stress are studied. It is found that the residual stress becomes increasingly compressive with increasing ion energy, with a slight concomitant fall in the coefficient of friction; neither the surface roughness nor the surface topography is affected. The data support the model, presented earlier, which proposes that defects, including dislocations, are generated in the surface by the implantation process and lead to the development of a work-hardened zone below the surface that enhances wear resistance.