The structure and properties of ZrAl(Y)N coatings deposited at various N2/Ar flow ratios

Abstract ZrAl(Y)N coatings were deposited on cemented carbide (YG8) and silicon (100) substrates by plasma-enhanced medium frequency reactive magnetron sputtering technique. The effects of yttrium addition and N 2 /Ar flow ratios on the composition, microstructure, mechanical properties, and oxidation resistance of ZrAl(Y)N coatings were characterized by scanning electron microscopy, X-ray diffraction and nano-indentation tests. The result shows that, with yttrium added to ZrAlN coating, the intensity of (111) peak apparently decreases and thus the preferred orientation changes to (200). The hardness and H 3 / E 2 increase by adding yttrium to the ZrAlN coating. The oxidation resistance of the ZrAlN coating is dramatically improved via yttrium addition. With the increase of N 2 /Ar flow ratio, the orientation of ZrAl(Y)N coatings changes and the crystallinity gradually lowers. The deposition rate continuously decreases with N 2 /Ar flow ratio increasing. Both the hardness and H 3 / E 2 of ZrAl(Y)N coatings are enhanced by increasing N 2 /Ar flow ratio. When N 2 /Ar flow ratio increases to 0.5, the hardness and H 3 / E 2 get the maximum values at 31.1 GPa and 0.178 GPa respectively. However, the oxidation resistance of ZrAl(Y)N coatings deteriorates slightly with N 2 /Ar flow ratio increasing.