Investigation of mechanical and microstructural properties of sputter-deposited Zr-Ni3Al coatings

Abstract

Zr-doped Ni3Al alloy coatings were deposited on a silicon substrate using DC magnetron cosputtering at a substrate temperature of 400 °C. The transformation of phase, microstructure, and surface topography was investigated using GIXRD, field emission scanning electron microscopy, and atomic force microscopy, respectively. The effect of zirconium (Zr) concentration on the microstructure and mechanical properties of Ni3Al coatings has been discussed. It is observed that the high concentration of Zr in Ni3Al coatings led to the evolution of microcracks that further contributes to increasing the surface roughness of the coatings. Results revealed that the Ni3Al coating without Zr content exhibited the highest hardness of 12.8 GPa. It is also found that with the increase in Zr content in host Ni3Al coatings, the hardness decreases, whereas the contact angle increases. Ni3Al coatings with 40 W Zr enrichment showed a hydrophobic nature with a contact angle of 101°.