Corrosion Inhibition of AD31 Alloy by Cerium Nitrate (III) and Sodium Metavanadate

Corrosion inhibition of aluminum alloy AD31 (AA6063) in aggressive chloride-containing acidic media by cerium nitrate (III), sodium metavanadate, and mixtures of thereof has been investigated by electrochemical and weight loss techniques. The inhibition effectiveness of cerium ions and cerium-vanadate mixtures has been shown. Weight loss tests in 0.5 M NaCl solutions with and without the addition of inhibitors were performed to determine the effect of the inhibitors on the extent of corrosion damage of the alloy surface. Electrochemical potentiodynamic polarization measurements were used to investigate the inhibition mechanism. The lowest values of corrosion currents (7.05·10-9 A/cm2) were observed in the presence of 3 mM Ce(NO3)3.