Selective electrodeposition of zinc–nickel alloy through porous medium

The ‘portable electrodeposition’ method described in this work differs from the conventional brush plating method in that it utilizes a reservoir that contains the electrolyte. A diffusion medium allows the cations to migrate to the working electrode surface (cathode) in continuous mode such that the coating is made selectively in the region, which comes in direct contact with the diffusion medium. The diffusion medium also prevents the working surface from being flooded with the electrolyte and dispenses the electrolyte in a more controlled fashion. Unlike conventional flow plating, this prevents the spillage of the electrolyte solution reducing environmental pollution and comparatively requires lower wattage power supply. To characterize the results of the above technique, zinc–nickel alloy coatings were made at different potentials using various types of diffusion media. The coatings were tested for chemical composition, galvanic protection, hardness, and porosity.