Corrosion of CuNi30Fe in artificial solutions and natural sea water: influence of biofouling

Abstract

The electrochemical behaviour of CuNi30Fe in natural sea water, artificial sea water, NaCl+Na₂SO₄, and NaCl solutions has been compared. Potentiodynamic polarisation curves, open circuit potential versus time plots, and current transients were recorded. Significant differences between the electrochemical responses of the alloy in the electrolytes used were detected. Corrosion products after various exposure times in-natural sea water and in artificial solutions were analysed using SEM and EDAX. Attachment of micro-organisms after exposure in natural sea water was examined by SEM. The effect of biofilms at early stages of formation on the corrosion process was also studied. The protective characteristics of the complex layers formed on the CuNi30Fe surface were found to be altered by microbial adhesion to the metal surface.