Cu redistribution study during the corrosion of AZ91 using a rotating ring-disk collection experiment

Redistribution of impurities during the dissolution of AZ91 and synthesized Mg-0.5Cu alloys were studied with rotating ring-disk collection experiments and stripping voltammetry. In solution, where the potential value of both alloys is far below the equilibrium potential values of Cu oxidation reactions, nonfaradic release of Cu particles led to the production of Cu ions which were subsequently reductively collected on an outer Pt ring. The collected Cu was analyzed and confirmed with stripping voltammetry. The results of this work support the notion that isolated Cu atoms or Cu-rich particles can be oxided in aerated solutions at low potential values, and generated Cu ions can be reductively redeposited on a Mg alloy surface.