An electrode array study of electrochemical inhomogeneity of zinc in zinc/steel couple during galvanic corrosion

The local electrochemical properties of anodic metal within a zinc/steel couple immersed in seawater was studied via an electrode array composed of zinc and mild steel wire sensors. It showed that the potential and current density distribution of zinc wires were inhomogeneous, and the main anodic area moved from the zinc wires adjacent to the steel wires and even further away. Also, some zinc wires behaved as secondary cathodes. The observed electrochemical inhomogeneity was attributed to the variation of distances between the zinc and mild steel wire sensors over the electrode array as well as their surface electrochemical status.