A comparative study of the structure and the corrosion behavior of zinc coatings deposited with various methods

The structure and the corrosion performance of Zn coatings formed by pack cementation and fluidized bed reactor at 250, 350, 380 and 400 degrees C have been studied. From this investigation, it turned out that these coatings are composed of two layers referring to gamma-FeIIZn40 and delta-FeZn10 phases of the Fe-Zn phase diagram. Furthermore, in the pack coatings, inclusions were detected, which are composed of Fe and Zn at almost equal concentrations. Concerning the corrosion, a mechanism of stress corrosion has been identified. The corrosion performance of the studied coatings is similar to that of the hot-dip galvanized coatings, although the deposition method is different. (c) 2005 Elsevier B.V. All rights reserved.