Physico-Chemical Properties of Zn-Ni Alloy from Alkaline Sulphate Bath Containing Tartrate

Abstract

The composition, properties, voltammetry studies and morphology of electrodeposited Zn-Fe alloy deposits obtained from an alkaline sulphate bath containing tartrate have been investigated. A bath containing high percentage of iron (20% wt.) produced an alloy with less percentage of iron (12% wt.) i.e. anomalous co-deposition process. The percentage of iron in an alloy decreased with temperature of the plating bath and thickness of the alloy deposit. The cathodic current efficiency depends on plating variables. Cyclic voltammetry studies indicate the mutual co-deposition of zinc with iron. Zn-Fe alloy showed a superior corrosion resistance than zinc coatings. Hardness of the alloy deposits increased with increase in iron content in the alloy. Smooth, uniform and fine grained deposits were obtained for the Zn-Fe alloy containing 20% Fe.