Oxide scale growth behavior of alumina-forming austenitic stainless steel exposed to supercritical water

The corrosion characteristics of a novel alumina-forming austenitic (AFA) steel exposed to 600 degrees C/25 MPa deaerated supercritical water (SCW) were investigated. The results show that the weight gain curves of the AFA steel follow parabolic law. A chromium-rich oxide scale containing reticular alumina is formed in the AFA steel, which contributes to the high corrosion resistance of the AFA steel. No continuous alumina scale is formed on the AFA steel with 2.5 wt% Al addition, which is attributed to the negative effects of B2-NiAl, Laves and sigma-FeCr precipitates on the continuity of alumina scale.