Biofilm inhibition and corrosion resistance of 2205-Cu duplex stainless steel against acid producing bacterium Acetobacter aceti

Abstract

Acid producing bacterium Acetobacter aceti causes pitting corrosion of stainless steel (SS). This work investigated the enhanced resistance of 2205-Cu duplex stainless steel (DSS) against biocorrosion by A. aceti in comparison with 2205 DSS using electrochemical and surface analysis techniques. With the addition of Cu to 2205 DSS, biofilms on the 2205-Cu DSS surface were inhibited effectively. The largest pit depth on 2205-Cu DSS surface in the presence of A. aceti was 2.6 μm, smaller than 5.5 μm for 2205 DSS surface. The icorr was 0.42 ± 0.03 μA cm−2 for 2205-Cu DSS in the biotic medium, which was much lower than that for 2205 DSS (3.69 ± 0.65 μA cm−2). All the results indicated that the A. aceti biofilm was considerably inhibited by the release of Cu2+ ions from the 2205-Cu DSS matrix, resulting in the mitigation of biocorrosion by A. aceti.