A Small Amount of Alloying Additions Applied in Hot Dip Galvanizing

Abstract

Investigating the changing quality of galvanized parts when pure zinc plated with other alloying additions. In the procedure of hot dip galvanizing, when pure zinc plated without other alloying additions, the corrosion resistance of zinc coating is poor, meanwhile the bath surface will produce a number of zinc dross, zinc ash, and this phenomenon will cause a waste of zinc, resulting in an increase in product costs, and the surface of product is relatively dark, the brightness is not enough, whilst sometimes even form a phenomenon of the formation of the Pan-color on the surface of the galvanized parts. However, when a proportion of aluminum or rare earth elements is added into melting zinc, the corrosion resistance of coating will be improved and much better than pure zinc galvanized parts;as the decrease of zinc ash, the cost will be reduced;synchronously the limititation of superficial quality above-mentioned will be improved. Via evaluating the superficial quality of galvanized parts and the corrosion resistance, the whole performance will be significantly improved when 0.5% aluminum and 1.5% rare earth elements is added into melting zinc.