Kirkendall Effect in Twin-Roll Cast AA 3003 Aluminum Alloy

The formation of an inhomogeneous structure with central segregation occurs in commercial twin-roll cast AA 3003 aluminum alloy. The segregations form as manganese, iron, and silicon-rich channels spread in the rolling direction. Diffusion of silicon occurs during annealing at 450 °C, and the formation and growth of voids due to the Kirkendall effect occur. The evolution of pores studied by scanning electron microscopy and X-ray computed tomography shows that pores are formed near original pure silicon clusters. Their coalescence and the formation of large voids in the central zone of the strip occur at longer annealing times.