Study on the corrosion mechanism of Zr-1Sn-xFe-0.2Cr-0.02Ni alloy in 500 °C super-heated steam with oxygen

Abstract

Zr-1Sn-xFe-0.2Cr-0.02Ni (x=0.3, 0.45, wt%) alloys were exposed in 500 °C super-heated steam with oxygen to investigate the effect of oxygen concentrations in the corrosion environment and Fe contents in the alloys on the corrosion behavior. Results showed that increasing the Fe contents from 0.3 % to 0.45 % and the oxygen concentrations from deaeration to 1000 ppb can both accelerate the corrosion of the alloys, and the mechanism was explored from the perspective of Fe and oxygen affecting the oxidation of alloying elements and the microstructure evolution of the oxide film.