Effects of strain localization on the corrosion behavior of ultra-fine grained aluminum alloy AA6061

Highlights: • Shear bands formed during ECAP possess a higher volume fraction of closely spaced precipitates than the matrix. • Shear bands are preferential sites for the initiation and propagation of intergranular corrosion. • The shear direction and planes are highly susceptible to pitting due to the accumulation of AlFeSi precipitates along this direction and this plane. - Abstract: The formation of shear bands during high strain deformation processes is known to promote grain refinement and better mechanical response. However, the literature on how shear bands affect corrosion of aluminum alloys, supported by relevant microstructure characterizations is scarce. Here we provide insight into precipitate aggregation phenomena in a partially recrystallized microstructure. We elucidate how shear bands affect the material's corrosion susceptibility and degradation mechanism. Our results demonstrate that shear bands, in ultra-fine grained aluminum alloys, are preferential sites for pitting and intergranular corrosion due to particle segregation.