Stress-assisted microbiologically influenced corrosion mechanism of 2205 duplex stainless steel caused by sulfate-reducing bacteria

In the present work, we studied the stress-assisted microbiologically influenced corrosion mechanism of 2205 duplex steel caused by sulfate-reducing bacteria (SRB) in simulated seawater environment. The results suggested that SRB have a significant influence on the pitting behavior of 2205 DSS, and stress promotes the MIC behavior. The mechanism proposes that the ferrite phases and high-residual stress regions manifest as the preferential anodic electron donor for SRB respiration due to the galvanic effect caused by the composing duplex phases, high-stress regions and low-stress regions; this outcome leads to the preferential dissolution of ferrite phases and high-stress regions.