Method for Studying Stabilization of Localized Corrosion on Carbon Steel by Sulfate-Reducing Bacteria Available to Purchase

Initiation of a corrosion pit in plain carbon steel (CS) was simulated by preconditioning a small area and a larger concentric area as an anode and cathode, respectively. Preconditioning was achieved by applying a galvanic current between the electrodes. During this initial step, the effect of sulfate-reducing bacteria (SRB) on resulting polarization of this artificial galvanic cell was investigated. The previously conditioned electrodes then were left short-circuited, and the naturally flowing galvanic current was measured using a zero-resistance ammeter. In the presence of SRB biofilms, an active and naturally stable galvanic cell was achieved. In sterile conditions, the coupling current either was unstable or very low. This technique was aimed at studying risk factors linking bacterial contamination to the onset of rapid pitting corrosion.