The oxidation behavior of 316L in simulated pressurized water reactor environments with cyclically changing concentrations of dissolved oxygen and hydrogen

The oxidation behavior of 316L stainless steel in the simulated pressurized water reactor primary water with cyclic exposure to hydrogenated and oxygenated water conditions was investigated by contact electric resistance, electrochemical impedance spectroscopy, scanning electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy techniques. The electrochemical resistance of the oxide film exhibits significant changes as the environment is shifted from hydrogenated water chemistry to oxygenated water chemistry and vice versa. However, in different hydrogenated periods (or oxygenated periods) with the same water chemistry, the electrochemical resistance of the oxide film is very similar. On the contrary, the oxide morphology and composition do not show obvious changes, and the oxide film thickness has a generally increasing trend. The reason for this phenomenon was also discussed.