The role of marine bacteria on corrosion behaviour of CuNi10Fe alloy in artificial seawater

The effects of different exposure conditions on the electrochemical behaviour of the CuNi10Fe alloy have been evaluated in artificial seawater at 19 °C with and without the mixed culture of heterotrophic marine bacteria under either aerobic or anaerobic conditions during 6 days’ measurements. This study employed electrochemical techniques such as linear and potentiodynamic polarization measurements and electrochemical impedance spectroscopy. The results obtained by electrochemical measurements have indicated that the corrosion resistance of the examined alloy is better in sterile AS under anaerobic conditions than under aerobic ones. However, the addition of the mixed culture of heterotrophic marine bacteria to sterile AS under aerobic conditions led to an increase in the corrosion resistance. A similar tendency in the corrosion resistance behaviour was observed for the CuNi10Fe alloy during the first 24 hours of exposure to the mixed culture of heterotrophic marine bacteria under anaerobic conditions, but after that period, a decrease was observed in the corrosion resistance attributed to bacteria activity.