Electrodeposition of Zn-Ni Alloy from Alkaline Sulphate Bath Triethanolamine and Mercaptopyridine

Electrodeposition of Zn-Ni alloy from non-cyanide alkaline sulphate bath containing triethanolamine (TEA) and mercaptopyridine (MPY) under optimized plating conditions such as bath pH, temperature current density and metal ion ratio in the bath produced an alloy deposit with the desired composition of 10-15 %wt. of nickel, alloy of this composition showed good adhesion, high hardness pore free, smooth, uniform and finer grained. Deposition potentials of Zn-Ni alloy lie between the potentials of individual metals. Increase in temperature density decreased the nickel content in the alloy deposit, which with increase in temperature and thickness of the alloy deposit increased nickel content in the alloy deposit. Alloy deposition followed a regular type of co-deposition.

Physico-Chemical Properties of Zn-Ni Alloy Deposits from an Acid Sulphate Bath Containing Ethanolamines

The composition, properties, structure and morphology of electrodeposited Zn-Ni alloy deposits obtained from an acid sulphate bath have been investigated. A bath having higher percentage of nickel (50%) produced an alloy deposit with low percentage of nickel (12%), the percentage of nickel in the alloy deposit increases with current density up to 40 A.dm-2, with further increase in current density, the percentage of nickel shows a downward trend, increase in temperature of the plating bath increases the percentage of nickel in the alloy deposit. The hardness of the alloy deposits increases with increase in nickel content in the alloy, the phase structure of alloy deposit shows the presence of α, η, δ and γ phases. The morphology of Zn-Ni alloy deposits shows uniform and finer grained structure.

Electrodeposition of Zn-Fe Alloy from Non-Cyanide Alkaline Sulphate Bath Containing Tartarate

Electrodeposition of Zn-Fe alloy from an alkaline sulphate bath containing tartarate has been carried out. The effect of plating variables on the composition of alloy and on cathodic current efficiency was studied. The cyclic voltammetric studies carried out to know the mutual co-deposition of zinc and iron. Hardness and the surface morphology of the alloy deposits were found to be dependent on the iron content in the alloy. An alloy containing 20% wt. Fe showed smooth, uniform and finer grained deposits. Under the optimum composition and operating conditions, Zn-Fe alloy deposition from alkaline sulphate bath containing tartarate followed anomalous depositing process.