Characterization of the Corrosion Resistance of Composite Peened Aluminum

Composite peening offers the opportunity to introduce ceramic blasting particles into metallic base material. By embedding Al${}_2$O${}_3$ particles, mechanical properties of aluminum can be improved. However, those surface modifications might negatively impact corrosion resistance and thus shorten the lifetime of components. This study analyzes corrosion properties of peened aluminum in chloride solution via immersion, scanning electron microscopy and polarization. The data of observed microstructures indicate that peening accelerates corrosion and that intergranular corrosion is the main force of degradation in contrast with pitting corrosion of monolithic aluminum.