The repassivation kinetics study of Alloy 800 in high-temperature pressurized water

The repassivation kinetics of Alloy 800 is studied in high-temperature pressurized water with different dissolved hydrogen (DH) and dissolved oxygen (DO) at 300 °C. The results demonstrate that under DO conditions, the cBV value increases with the rise of DO concentration; and under DH conditions, the cBV value passes through a local maximum at DH = 1.0 ppm. In addition, the repassivation results in the present work confirm the applicability of the slip-dissolution model for explaining stress corrosion cracking in high-temperature pressurized water by means of electrochemical measurement. Compared with other methods of evaluating stress corrosion cracking susceptibility of engineering materials, studying the repassivation kinetics by rapid scratch technique is a more economical and time-efficient evaluation method for nuclear materials in high-temperature pressurized water.