Pitting corrosion of duplex stainless steels

This study showed the complex interactions of alloying elements and their prevailing microstructure on the pitting corrosion. This interaction was illustrated by electrochemical tests of three grades of wrought duplex stainless steels. It was shown that SAF2507 had the highest pitting potential, followed by SAF2205 and SAF2304. However, SAF2205 had higher corrosion potential than SAF2507. SAF2205 and SAF2507 were immune to pitting, while SAF2304 was susceptible to pitting. It was also found in the experiment that the austenite-ferrite interface was the most susceptible to corrosion, followed by the austenite and finally the ferrite phase.