The difference in preferential corrosion of 2205 duplex stainless steel induced by Pseudomonas aeruginosa between full and alternate immersion

The difference in preferential corrosion of 2205 DSS between full and alternate immersion induced by Pseudomonas aeruginosa was investigated. Different from the inhibition in pitting corrosion by alternate immersion in abiotic medium, corrosion acceleration by P. aeruginosa was further enhanced with the transition from full immersion to alternate pattern. Pitting sites focused on α phase and phase boundaries during full immersion in biotic medium, but they distributed irregularly under alternate immersion. These differences were closely related to different attachment behavior of P. aeruginosa between two immersion patterns, and the corresponding mechanisms were proposed. • Pitting corrosion of 2205 DSS under alternate and full immersion is studied. • Pitting corrosion is inhibited by alternate immersion in abiotic medium. • Corrosion acceleration by P. aeruginosa is further enhanced during alternate immersion. • Pitting sites between full and alternate immersion are quite different. • The relationship between bacterial attachment and pitting sites is elaborated.