Pulse Electroplating of Gold-Nickel Alloys: Morphological and Aesthetic Improvement Compared to DC

The use of pulsed current is well known as a research tool to study the electrodeposition mechanism of metals, however, it was realized that this method could provide a means to improve the properties of deposits. Electrodeposition of gold or its alloys is not only used in the electronics industry due to its conductive and anti-corrosive properties, but also as a final layer due to its aesthetic properties. In this study we focused on a cyanide gold-nickel bath, among the most frequently used in the electroplating industry intended for the decorative sector. The use of modulated currents has proven to be an effective methodology to be able to control and improve the chemical and physical characteristics of metal deposits. Deposits obtained through pulsed currents have a smaller grain size and a more homogeneous surface, both at the level of thickness dispersion on the surface and at the roughness of the samples themselves. A direct consequence of the above results is the improvement of the aesthetic finish of the workpieces with an increase in brightness as well as anti-corrosive properties.