The hot-dip-galvanizing process involves reaction between the solid substrate and the molten bath. The constituents of the steel and the molten bath influence the formation of the interfacial layer and its reaction kinet-ics. In Zn-bath galvanizing, Zn reacts with the substrate (Fe) to form a coating consisting of Fe-Zn Inter-Metallic Compounds (IMC). When Al is added into the Zn-bath (Zn-AI eutectoid composition), vigorous reaction between Fe and Al takes place resulting in rapid growth of the reaction layer, exhibiting porosities and outbursts, leading to un-satisfactory quality of coating.
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