Mechanical properties of multilayer TiAlN/CrN coatings deposited by cathodic arc evaporation

The results of the investigations of multilayer TiAlN/CrN coatings deposited using cathodic arc evaporation applying TiAl (50∶50 at-%) and elemental Cr cathodes are presented. The bilayer TiAlN+CrN thickness was ∼250 nm with the thickness ratio of TiAlN/CrN layers of approximately 1∶1. The atomic ratio of Ti/(Al+Ti) in the coating was 0·60. As the reference, the monolayer TiAlN and multilayer TiAlN/TiN coatings were selected. All the coatings were deposited on CrN sublayer to reduce their stress and improve their adhesion. The investigated coatings show good adhesion in the range 80-90 N. The TiAlN/CrN coating shows a lower friction coefficient and a significantly lower wear rate than those of reference coatings (more than 10 times).