Mechanical properties dependence on the modulation period in multilayered TiN/ZrN coatings

Abstract

Abstract This article presents results from a study on the properties of nanostructured multilayered TiN/ZrN coatings with different modulation periods deposited by cathodic-arc evaporation from Ti and Zr targets in nitrogen atmosphere on high-speed steel substrates. The thickness of the TiN-ZrN bilayers varied from 12 nm to 52 nm depending on the rotation speed of the holder. In order to investigate the effect of heat treatment on the mechanical and structural properties, the multilayer ZrN/TiN coatings were annealed in Ar atmosphere at different temperatures for two hours. The surface morphology, elemental composition, nano-hardness and adhesion strength of the as-deposited and annealed coatings were analyzed by scanning electron microscopy complemented with energy dispersive X-ray spectroscopy analysis, and nanoindentation and micro-scratch tests. The results obtained show that the mechanical properties of multilayer TiN/ZrN coatings are considerably improved in comparison to those of the monolayer ZrN and TiN coatings.