Comparative study of surface roughness and tribological behavior during running-in period of hard coatings deposited by lateral rotating cathode arc

This study focuses on the influence of surface geometry of hard coatings on tribological behavior. TiN, TiAlN, AlTiN and nanocomposite (nc-Ti1−xAlxN)/(a-Si3N4) (nACo) coatings were deposited by means of the lateral rotating cathode arc method on high speed steel (HSS) substrates. Surface topology (area of 50 μm × 50 μm, 10 μm × 10 μm and 5 μm × 5 μm) investigations by the atomic force microscopy (AFM) revealed that for all types of coatings the non-Gaussian height distribution function (HDF) is mainly due to the macroparticles. Factors and mechanisms affecting the value of the coefficient of friction (COF) during the running-in period were discussed.