Development of a Highly Durable Anode for Electrogalvanizing Lines

Abstract

We have developed highly durable IrO₂-Ta₂O₅/Ti electrodes as an oxygen evolution anode in electrogalvanizing lines (EGLs). The morphological and compositional changes of the IrO₂-Ta₂O₅ coating during anodic electrolysis have been investigated in order to improve the durability of the electrode in commercial EGLs. Based on the experimental findings obtained, the deterioration mechanism of the coating layer and the dominant factor to determine the electrode lifetime were examined. A key point to prolong the lifetime is the corrosion inhibition of the titanium substrate, which is induced by the penetration to the coating layer. The densification of the coating layer and the formation of a corrosion-resistive interlayer between the coating layer and the titanium substrate have successfully achieved the improved durability. The performance of the advanced IrO₂-Ta₂O₅/Ti electrode is shown.