Corrosion behaviour of electro-deposited zinc-iron alloy coatings on mild steel

Zinc-iron alloy was electrodeposited using zinc dross as anode. Zinc dross is an unwanted material produced during galvanizing. Two types of zinc dross, one with 9.2% iron and other with 2.7% iron, were used. During electroplating, cathodic efficiency was measured and it was observed that cathodic efficiency was low in case of zinc dross bearing high iron content. Corrosion potential determined from polarization curves revealed that the coating produced by using zinc dross I was noble (-10] 5 mV) to all other alloy coatings obtained using zinc dross II and pure zinc. Polarization tests as well as atmospheric corrosion tests indicated that coating obtained through zinc dross I was more corrosion resistant.