Corrosion of Stainless Steel by Sulfate-Reducing Bacteria — Electrochemical Techniques

Accelerated electrochemical testing of AISI(1) 304L, 316L, 316, 430, 409, Sandvik† 1802, SX 3CR12, and a mild steel was performed in three cultures of sulfate-reducing bacteria (SRB). The tests were conducted in order to ascertain whether SRB were capable of bringing about corrosion of the stainless types of alloys. In all cases, the pitting resistance of the alloys was found to be lower in cultures of SRB. This manifested itself as a decrease in Ecorr, an increase in ipass, the formation of an active peak, and a decrease in the passive range. Sulfide-induced pits were initiated at lower potentials than those associated with chloride pitting.