Effects of dissolved oxygen on the oxide scales formed on ferritic-martensitic steel T12 exposed to supercritical water

摘要

The oxidation behavior of T12 after exposure to 560 degrees C/25 MPa supercritical water with different dissolved oxygen contents was investigated. The weight gain increases while the resistance of the oxide scale decreases with the increasing dissolved oxygen content. The oxide scale is a typical multi-layered structure including a Fe-rich outer layer and a Cr-rich inner layer. The Cr-rich hematite layer oxide was observed on specimen tested at high dissolved oxygen. The possible oxidation mechanism was proposed and the effects of oxygen on the oxidation of alloys in supercritical water were discussed.