Interplay of microstructural features in Cr1−xAlxN and Cr1−x−yAlxSiyN nanocomposite coatings deposited by cathodic arc evaporation

The interplay between the deposition geometry, the chemical and phase composition, the crystallite size, the lattice strain and the direction and the degree of the preferred orientation of crystallites was investigated in the Cr1−xAlxN and Cr1−x−yAlxSiyN nanocrystalline coatings and nanocomposites, which were deposited in cathodic arc evaporation process at different positions of substrates in the deposition apparatus. The different positions of the substrates affected primarily the distance between the samples and the cathodes and consequently the chemical and phase composition of the coatings, the crystallite size, the lattice strain and the preferred orientation of crystallites. In the Cr1−xAlxN coatings, the dominating cubic crystallites were preferentially oriented with their 〈111〉 direction perpendicular to the sample surface; this out-of-plane preferred orientation of crystallites was accompanied by a strong in-plane texture. In the Cr1−x−yAlxSiyN coatings, a strong inclination of the {111} texture from the normal direction and a decay of the in-plane preferred orientation were observed in cubic crystallites with increasing silicon (and aluminium) contents.