Structure and properties of Ti–Al–Y–N coatings deposited from filtered vacuum-arc plasma

Ti_0.5Al_0.5N coatings with a small amount of Y (up to 1 at.%) were deposited by filtered vacuum arc plasma at pulsed high voltage negative substrate bias potential with amplitude up to 2.5 kV and their microstructure was studied. X-ray fluorescence analysis showed that this deposition method allows ensuring well the conformity of the elemental composition of the metallic components of cathodes and films. X-ray diffraction measurements of the films with yttrium revealed a solid solution (Ti,Al)N phase with a cubic NaCl-type structure as the only crystalline phase. The films deposited with an amplitude of the substrate bias potential in the range of 1–1.5 kV were characterized by a strong axial texture [110]. In these films an increase of the yttrium content leads to the reduction of the nitride lattice parameter and growth of coherent scattering zone dimension as well as to a decrease of the surface roughness. Coatings containing 1 at.% Y exhibited high hardness of 32–36 GPa and oxidation resistance.