MARINE CORROSION BEHAVIOR OF THE COPPER ALLOY B10 UNDER SULFATE-REDUCING BACTERIA BIOFILM

The corrosion of copper alloy B10 induced by sulfate-reducing bacteria (SRB) was studied in seawater. Electrochemical impedance spectroscopy (EIS) was used to analyze the electrochemical corrosion behavior. The surface properties of the corrosion samples were analyzed by electronic microscope (SEM). Through circuit modeling, The results confirmed that the extensive localized corrosion activity of SRB is due to a formed biofilm and a porous iron sulfide layer on the metal surface. SEM revealed the presence of SRB increased the pitting corrosion that maybe attribute to the inhomogeneous distribution of SRB biofilms. The results indicated that the existence of SRB hold back the formation of passive film on the B10 surface and increased the corrosion rate.