Scale removal oxidation behavior of metal in supercritical water modeled by cellular automaton

Corrosion and oxidation of structure material in supercritical water are specific and an important issue in the nuclear industry. A scale removal cellular automaton model was proposed to investigate the development of a continuous oxide layer of Inconel 625 in supercritical water at 24.8 MPa and 600 °C. This study presented influence of the reaction behavior of oxidation, scale removal effect, and transport ratio of oxygen and metal ions on the corrosion and oxidation process with different conditions. The formation of the spinel is simulated at mesoscopic level. The developed model is also mapped with the laboratory experimental data from a supercritical water loop.

► A scale removal CA model was proposed for Inconel 625 in SCW at 24.8 MPa and 600 °C. ► This study shows influence of the oxidation reaction, scale removal effect. ► The duplicate oxide layer in the CA model fits the experimental observation. ► The trend of the simulated results and experimental results follows the parabolic law.