An approach to improve the oxidation resistance of a Ni-28W-6Cr alloy by hindering the oxygen vacancy-mediated oxidation

Abstract In this work, an approach to improve the oxidation resistance of a Ni-based alloy was proposed by doping a high valence metal element into the oxides. Oxidation kinetics of Ni-28W-6Cr alloys with 0−0.2 wt.% Zr at 850 °C show that Zr can significantly decrease the oxidation rate of the alloy and the thickness of the inner oxide. Zr charged +4 prefers to segregate in the inner NiWO4 by replacing Ni2+, which inhibits the formation of oxygen vacancies and reduces the oxygen diffusion pathways, improving the oxidation resistance of the alloy.