抄録
The wear behavior of titanium nitride (TiN) films with island-like nanostructures was investigated. The films were deposited on a tool steel SKD61 substrate by an ion beam assisted deposition (IBAD). When the substrate was fixed perpendicular to the ion beam, the surface morphology of the film was smooth. In contrast, the out-of-plane rotation of the substrate during IBAD induced island-like nanostructures on the film surface. The size of island increased with a decrease in rotational rate of substrate. The wear behavior was investigated by ball-on-disc tests. In the case of sample coated with smooth TiN film, the friction coefficient increased gradually in test. On the other hand, in the case of sample coated with island-like nanostructured TiN film, the friction coefficient decreased compared with sample coated with smooth TiN film. These results mean that the existence of island-like nanostructure reduce the friction. Moreover, the significant decrease in friction coefficient and wear volume was caused by not but high hardness but also large surface roughness of film.
