A Novel Characterization Method for Hard Coatings: Preliminary Results with TiN

Pin-on-disc method is increasingly used to evaluate the tribological behavior of thin hard coatings. At present, ISO 18535 is the only standard applying to hard coatings tribology and it prescribes that investigations do not extend past the coating failure. This approach followed by many researchers is inadequate though for a complete characterization of a coated system. A novel approach is proposed in this paper, at a preliminary stage, to characterize coated systems thoroughly. Friction curves with a suitable shape are resorted to, so that two representative friction coefficients can be extracted, one before and the other after coating failure. Results with a PVD TiN coating are presented showing that it is possible with this coating to get friction curves with the desired shape in specific testing conditions.