The corrosion electrochemical behavior of a water-borne epoxy coating pigmented with aluminum flake on carbon steel with artificial scratch defect was studied in 3.5% NaCl solution using electrochemical impedance spectroscopy(EIS)and scanning vibrating electrode technique(SVET).The results indicated that the defect presented anodic electroactivity at the initial stage of immersion,which extended gradually with time from the scratch into the neighboring coating,lowering the coating impedance.With further immersion,however,the electroactivity of the coating/steel interface decreased significantly due to the self-repairing of the corrosion products,causing an obvious increase of the coating impedance.In the later period of immersion,more scattered electroactive areas appeared under the coating because of the penetrating of corrosive species to the surface of substrate,which led to the decrease of coating impedance,showing the delamination and damage of the coating.
water-borne coating, aluminum flake, corrosion, self-repairing, EIS, SVET
Online Available Date
Li-li XUE, Li-kun XU, Qing-fen LI, Hong-qing SONG, Wen-Juan ZHOU, Guang-Zhang CHEN.
Corrosion Electrochemical Behavior of Aluminum Flake Pigmented Water-Borne Epoxy Coating on Carbon Steel in NaCl Solution[J]. Journal of Electrochemistry,
Available at: https://jelectrochem.xmu.edu.cn/journal/vol13/iss2/12