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.

Nickel plating aluminum galvanic corrosion.

Porosity in base metal causing plating problems february 3 2017. Electroless nickel plating can provide a robust solution to corrosive attack across a range of corrosive mechanisms including galvanic corrosion chemical attack and erosion. Galvanic corrosion also called bimetallic corrosion or dissimilar metal corrosion is an electrochemical process in which one metal corrodes preferentially when it is in electrical contact with another in the presence of an electrolyte a similar galvanic reaction is exploited in primary cells to generate a useful electrical voltage to power portable devices. 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.

Galvanic corrosion some times called dissimilar metal corrosion is the process by which the materials in contact with each other oxidizes or corrodes. There are three conditions that must exist for galvanic corrosion to occur. First there must be two electrochemically dissimilar metals present. Typically we are plating small precision machined housings from 6061 t6 aluminum alloy.

The chart below shows how different plating materials react to one another with regard to their galvanic potential. Zangari in encyclopedia of interfacial chemistry 2018. The plating is typically electroless nickel and then gold.