Effects of Mg And Cu on Al Corrosion In Alkaline Solutions

In the effort to understand the influence of Mg and Cu segregated to grain boundaries on the Intergranular Stress Corrosion Cracking (IGSCC) of Al alloys, the electrochemical properties of surfaces prepared to simulate the composition of a grain boundaries have been examined using a combined electrochemical/surface analysis system. This paper describes the corrosion responses of pure Al, pure Al implanted with Mg and Cu, and some Cu containing Al alloys. The samples were tested in a potential 100 mV anodic of the open-circuit potential. Both Cu and Mg were found to influence the corrosion in different ways.