Microstructural influence of sigma phase on pitting corrosion behavior of duplex stainless steel/NaCl electrolyte couple

This study reports the effects of the sigma phase on pitting corrosion behavior of thermally-aged duplex stainless steel (DSS). Analysis via structural, morphological, and electrochemical characterizations was performed. The corrosion assessment includes a potentiodynamic test in 1 M NaCl solution at temperatures of 25, 40, and 65 degrees C. 3D roughness images were taken and compared for all the specimens before and after the corrosion test. The potentiodynamic test combined with the method of optical profilometry was found to be a successful approach to evaluate the evolution of surface degradation mechanisms due to pitting corrosion.

Automated summary

This study investigates the effects of the sigma phase on pitting corrosion behavior of thermally-aged duplex stainless steel, using structural, morphological, and electrochemical characterizations. Potentiodynamic tests in 1M NaCl solution at different temperatures were conducted, along with 3D roughness image comparisons for before and after corrosion tests. The study concludes that potentiodynamic tests combined with optical profilometry are a successful approach to evaluate surface degradation mechanisms due to pitting corrosion.