Pitting Corrosion of Austenitic Stainless Steels in Electroactivated Water

Abstract

The pitting corrosion behavior of austenitic stainless steels (SSs) UNS S30400 and UNS S31600 exposed to electroactivated water (EAWA) (oxidation–reduction potential [ORP] 1100±15 mV and pH 4.5±0.2) was evaluated by gravimetric tests, linear and cyclic potentiodynamic polarization (CPP), electrochemical impedance spectroscopy (EIS), atomic force microscopy (AFM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). Gravimetric and electrochemical results for corrosion rates indicate a good corrosion resistance of the tested SS. However, localized pitting corrosion appears after 1 week of exposure to EAWA, as was corroborated by the results of both corrosion rate and surface analysis. Special care must be taken for the sanitization of SS surfaces used in medical installations to avoid their corrosion when EAWA is applied as a disinfectant.