Effect of test media on the crevice corrosion of stainless steel by sulfate reducing bacteria

The potential for crevice corrosion of UNS30400 stainless steel in the presence of sulfate-reducing bacteria (SRB) was studied in different media. Immersion studies found crevice corrosion to occur in test media supplemented with high chloride levels and SRB present for crevice gaps of ~3 μm. Electrochemical measurements showed high susceptibility to corrosion in this particular medium, demonstrated by a negative shift of open circuit potential, increased corrosion current and the lowest passivity breakdown potential. Overall, the results showed that test media can play a critical role in the crevice corrosion of stainless steel in the presence of SRB.