Electrodeposition of Zn-Ni-Cd ternary alloys from acetate bath

Electrodeposition of Zn-Ni-Cd ternary alloys on steel substrates has been c arried out under different conditions of concentration of electrolyte, temp erature and current density. The effects of these parameters on the cathodi c potential, cathodic current efficiency and composition of the deposits ha ve been investigated. The bath is characterized by high current efficiency and shows feature of anomalous co-deposition. Zn and Cd deposited preferent ially as compared to Ni. Increasing current density and temperature enhance the rate of Cd deposition but suppress that of Zn deposition. Ni content i n the deposits is hardly affected by changing these variables. Surface morp hology of the deposits has been examined by scanning electron microscopy an d crystal structure by X-ray diffraction analysis.