The effect of Desulfovibrio caledoniensis and Pseudomonas aeruginosa on the corrosion behaviour of 70Cu-30Ni alloy

This work investigated the effect of Desulfovibrio caledoniensis (D. caledoniensis) and Pseudomonas aeruginosa (P. aeruginosa) on the microbiologically influenced corrosion (MIC) behaviour of 70Cu-30Ni alloy using surface analysis and electrochemical techniques. The results demonstrated that the mixed medium containing D. caledoniensis and P. aeruginosa further accelerated the MIC of 70Cu-30Ni alloy compared to the single species medium. The addition of exogenous pyocyanin (PYO) to the D. caledoniensis medium increased the maximum pit depth on 70Cu-30Ni alloy from 5.40 μm to 6.59 μm, and the corrosion current density (icorr) increased by one order of magnitude. From the perspective of bioenergetics and extracellular electron transfer (EET), the comprehensive MIC mechanism of 70Cu-30Ni alloy induced by D. caledoniensis and P. aeruginosa was proposed.