The in-situ scratching repassivation behavior of steam generator tube material in high-temperature pressurized water

摘要

The repassivation kinetics of steam generator tube material Alloy 800 and 690 are studied in high temperature pressurized water with different dissolved hydrogen (DH) and dissolved oxygen (DO) at 300°C. The results demonstrate that under DO condition the cBV value increases with the rise of DO concentration; and under DH condition, 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 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 more economical and time-efficient evaluation method for nuclear materials in high temperature pressurized water.