Corrosion of Al-Zn Alloy Coating by Flame Splay Methods in Flowing Seawater near Freezing Point

Abstract

Corrosion behavior of Al-Zn alloy coating on aluminum alloy substrate by flame splay methods in seawater was investigated using a jet-in-slit testing apparatus. Light brown corrosion product was observed on the surface of the specimen tested in static seawater, however, little corrosion occurred. On the other hand, white corrosion oxide product was observed on the surface of the specimen tested in flowing seawater near freezing point. The difference in the corrosion morphology was caused by the crack of the protective film generated near freezing point and the increase of oxygen supply onto the defected surface due to flowing of solution.