Polarization studies of Cu-Co alloy coatings

Polarization characteristics of the processes of Cu, Co and Cu-Co alloy electrodeposition from ammonium sulphate containing supporting electrolyte and their morphologies are investigated as a function of Cu²⁺ and Co²⁺ ions concentrations. By application of energy dispersive spectral analysis, (EDSA), including X-Ray analysis and SEM, data are obtained about the morphology and element composition of the deposited Cu-Co alloy coatings. The optimum electrolyte composition and the deposition potentials for production of quality coatings are determined. It is found that the conditions leading to cobalt content increase in the alloy result in improvement of the Cu-Co coating structure they are more fine-crystalline and homogeneous. These are compositions in the ranges: for CuSO₄ up to 25g dm^-3 and for CoSO₄ from 25 to 50 g dm^-3. It is found that in the developed electrolyte the maximum Co content is about 50-55.