Abstract
Previous studies and field experiences have shown that duplex stainless steels (DSS) may become susceptible to general corrosion and stress corrosion cracking in high pH caustic solutions. The rate of corrosion may further be affected by the presence of sulfide ions in caustic solutions. Moreover, since different grades of DSSs are characterized by different chemical compositions and microstructure, these parameters may have influence on the corrosion properties of duplex stainless steels. This difference in the corrosion properties is mainly attributed to the change in the passivation behavior of steel. The present study is aimed at investigating the corrosion properties and electrochemical behavior of different grades of DSS (2304, 2205 and 2101) with varying chemical composition and microstructure in high pH caustic and sulfide containing caustic solutions at different temperatures.