Study of the electrochemical behavior of Al-Zn-In based sacrificial anodes in sea water

Abstract

Cathodic protection is one of the most commonly used methods to protect steel structures immersed in seawater. This mode of protection may be used alone or associated with a coating, such as paint systems. This work aims to determine the durability of this protection system. We have studied the sacrificial nature of anodes made from Al-Zn alloy. The different materials used have been subjected to stationary and non-stationary electrochemical tests, especially electrochemical impedance spectroscopy (EIS), which is then characterized by EDX and SEM. In the case of sacrificial anodes, the results have highlighted the conditions of activation and passivation of these anodes, which are of particular industrial interest. A relationship has been established between the functioning of the studied anodes and the nature of the corrosion products. and revealing three areas of resistance and suggesting complex mechanisms for localized corrosion.