Micro-scale abrasion testing of PVD TiN coatings on conventional and nonledeburitic high-speed steels

Micro-scale abrasion testing has been used to evaluate the wear resistance of PVD TiN and Ti/TiN coatings on conventional and nonledeburitic high-speed steels. The experimental data were analysed with a model employing only the inner diameter of the wear scar and independently measured wear coefficients for the substrates. A new simplified method involving the measurement of a single crater and the evaluation of coating thickness by SEM and image analysis was also used. Both approaches were found to be equally accurate and yielded results which were not statistically different. The simplified method can be recommended for initial and/or rapid assessment of coating performance, or for small samples or small coated areas on which only a single test is possible. The results were augmented by SEM observations of the wear mechanisms.