Electrochemical Noise Evaluation of Metal Cation Effects on Galvanic Corrosion of Aluminum Alloys in Low Concentration of Chloride Ion Containing Solutions

The effect of metal cations on the galvanic corrosion behavior of A3003 aluminum alloy in low concentration of chloride ion containing solutions (tap waters) was examined by electrochemical noise impedance. The electrochemical noise impedance and conductance were calculated by the power spectrum density of the galvanic current and potential. The sum of the galvanic current during galvanic corrosion tests was suppressed by the addition of Ca2+, Zn2+ and Ni2+, while it was increased with Mg2+ addition. These results may be explained by the passive film structure changes due to the metal cations. The results obtained in this study indicate that metal cations play an important role in the corrosion behavior of A3003 aluminum alloys in tap water.