Utilisation of Electrochemical Methods for Characterization of Some Corrosion Inhibitors for Steel and Copper

Abstract

The effect of chromate and molybdate on the corrosion inhibition of copper and steel has been investigated in two eutectics solution at room temperature. We used stationary electrochemical methods and optical microscopy for the characterization of these materials. For steel, the molybdate inhibitor appears less efficient than the chromate one; for copper the polarization curves present an anodic passivation domain only in the chromate inhibited medium. The possibilities of galvanic coupling between them were simulated. This simulation has shown that, between copper and steel, the risk is more important in chromate medium than in molybdate one.