SEM study of defects in PVD hard coatings

Hard coating defects are produced by foreign particle contamination on substrate surface before and during coating, or due to arcing. In this work, CrN, TiAlN and CrN/TiAlN multilayer hard coatings were prepared by thermoionic arc ion plating deposition system BAI 730 (Balzers) and by sputter deposition in CC800 (CemeCon). We investigated the concentration of defects, its size and structure after tool steel substrate surface pretreatment (polishing, ion etching) as well as after deposition by means of atomic force microscopy (AFM) and scanning electron microscopy (SEM).