Effect of Solution Treatment on Corrosion Behavior of 254SMO Austenitic Stainless Steel

The effects of solution treatment on electrochemical corrosion of 254 SMo stainless steel in 3.5 g/L Na Cl solution were studied by potentiodynamic scanning(PDS) and electrochemical impedance spectroscopy(EIS). The microstructure of the steel after heat treatment was observed by OM to explore the relationship between microstructure and corrosion. The results show that with the increase of solid solution temperature, the precipitates dissolve in the grain, the grain becomes larger, and the number of twins increases; the corrosion rate increases firstly and decreases subsequently with the increase of aging temperature. The corrosion rate of the steel heat treatment at 1150 ℃ is fastest. Solution treatment at 1250 ℃can gain good corrosion resistance and homogeneous microstructure.