Characterization and corrosion behavior of F6NM stainless steel treated in high temperature water

摘要

Graphical abstractSchematic of the formation of oxide film on F6NM stainless steel exposed to high temperature water.Display OmittedHighlights•F6NM steel was exposed to 350°C water condition for different times, and the characterization of oxide film was analyzed.•Corrosion behaviors of oxide film was investigated by electrochemical impedance spectra (EIS).•The mechanism of the formation process of the oxide film was discussed.AbstractF6NM martensitic stainless steel was exposed to 350°C water condition for 500, 1500, and 2500h to simulate pressurized water reactor (PWR) condition. The characterization and corrosion behavior of the oxide film were investigated. Results indicate that the exposed steel surface formed a double-layer oxide film. The outer oxide film is Fe-rich and contains two type oxide particles. However, the inner oxide film is Cr-rich, and two oxide films, whose thicknesses increase with increasing exposure time. The oxide film reduces the corrosion behavior because the outer oxide film has many crack and pores. Finally, the mechanism and factors affecting the formation of the oxide film were investigated.