SVET method for characterizing anti-corrosion performance of metal-rich coatings

The galvanic interaction between a metal-rich coating and the underlying metal substrate was characterized by a new analysis method based on the scanning vibrating electrode technique (SVET). The total anodic current at various immersion periods was evaluated by integrating the anodic current density on SVET maps. Zinc-rich paints (ZRPs) coated on a steel panel were used to demonstrate the experimental approach. The anti-corrosion performance of the ZRP was analyzed based on the integrated anodic current and the experimental EOC–iInt diagram. Closely correlative behaviour was found between the integrated anodic current and the open-circuit potential.