Study of corrosion behavior of sprayed zinc-aluminum (ZAZA) coatings in a marine environment

Abstract Zinc-aluminum coatings were prepared; parts of them were sealed with an organic coating; and the behavior and mechanism of corrosion were studied by means of in situ plates test, salt spray test, and electrochemical impedance spectroscopy. A scanning electron microscope was used to assess the surface of the zinc-aluminum coatings, which showed roughness and some defects that would reduce the protective effect. Organic coatings improve the protective effect by sealing the defects of the metal coating. A multilayer structure is not only expensive but would also destroy the continuity of the coating if the zinc corrodes.