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

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 degrees 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.

Automated summary

The study demonstrates that doping zirconium into Ni-28W-6Cr alloys can significantly improve the oxidation resistance of the alloy by reducing the oxidation rate and inner oxide thickness, as Zr charged +4 prefers to segregate in the inner NiWO4, inhibiting oxygen vacancies formation and reducing oxygen diffusion pathways.