Corrosion inhibition of copper-zinc alloy by cationic surfactants in seawater

摘要

THE EFFECT of decyl ammonium acetate, DAA, and tetra ethyl ammonium iodide, TEAL, on the corrosion of copper-zinc alloy in seawater has been investigated. The inhibitive efficiency of these compounds determined form both polarization resistance and potentiodynamic measurements follow the order DAA>TEAL, and increase with increasing concentration. The potentiodynamic behaviour for the alloy shows, in the forward sweep, two anodic peaks corresponding to the formation of ZnO and the Zn (II) soluble species. On further increase in anodic potential, two additional peaks appeared before the passivation region: one is assigned to the formation of Cu_2O and CuCl, while the second is related to the formation of CuO. The back sweep shows an activation anodic peak and three cathodic peaks before attaining the hydrogen evolution potential. The addition of the tested inhibitors will affect the magnitude of these peaks.