Nickel Plating Aluminum Galvanic Corrosion

Porosity in base metal causing plating problems february 3 2017.

Nickel plating aluminum galvanic corrosion.

Galvanic corrosion is an electrochemical process in which one metal corrodes preferentially to another when both metals are in electrical contact in the presence of an electrolyte. The plating is typically electroless nickel and then gold. Electroless nickel plating en can be applied to a wide range of basis metals including steel copper brass and aluminum alloys. There are three conditions that must exist for galvanic corrosion to occur.

First there must be two electrochemically dissimilar metals present. The chart below shows how different plating materials react to one another with regard to their galvanic potential. Galvanic corrosion some times called dissimilar metal corrosion is the process by which the materials in contact with each other oxidizes or corrodes. Iron group metals nickel cobalt iron nickel plating is among the most common electrodeposition processes and is used mostly as a part of a multilayered system designed to increase wear and corrosion resistance and also able to function as a diffusion barrier.

Typically we are plating small precision machined housings from 6061 t6 aluminum alloy. I am having plating problems such as visible peeling and blistering and voiding in areas. Zangari in encyclopedia of interfacial chemistry 2018.