Oxidation Processes and Involved Chemical Reactions of Corrosion-Resistant Alloys in Supercritical Water

Corrosion continues to be a major challenge in developing supercritical water-cooled reactor and supercritical water oxidation systems. Corrosion behaviors of candidate alloy materials used in these environments are significantly affected by the properties of oxides formed on alloy surfaces. This work presents a comprehensive review of the oxidation processes and involved chemical reactions of corrosion-resistant alloys in supercritical water. The oxidation process of an alloy in supercritical water is proposed to have two stages, and chemical reactions at these two stages are described in detail. The transitions of Cr/Ni/Fe oxides and the formation mechanism of oxide film are analyzed comprehensively. Moreover, the diffusion property, protection effect, and stability of oxides in supercritical water are summarized systematically.