The localized corrosion of Al at engineered Cu islands

Arrays of engineered copper islands on an aluminum thin-film matrix have be en employed to investigate the role of copper in localized corrosion of Al- Cu alloys. When exposed to dilute NaCl solutions, the engineered samples co rrode with a morphology similar to that observed in second-phase particles in real alloys. In-situ fluorescence microscopy allows the observation of o xygen reduction at copper islands during corrosion of the underlying alumin um thin-film matrix. The spacing between engineered copper islands was foun d to strongly influence the corrosion rate of the surrounding matrix.