Shear banding and recrystallization texture development in a multilayered Al alloy sheet produced by accumulative roll bonding

A commercial purity Al alloy and an Al–0.3 wt.% Sc alloy, the latter in either the supersaturated or artificially aged condition, were accumulative roll bonded to produce 0.5-mm-thick sheet consisting of multiple alternating layers of Al and Al(Sc). The deformation mechanism of these two combinations was strongly influenced by the relative hardening behaviour of the adjacent layers. For the Al/Al(Sc)aged material, a higher magnitude of in-plane shear stress, well exceeding the flow stress of Al(Sc), was operative at the interface between layers. This resulted in through-thickness shear banding and a marked curvature of the layers in the RD–ND sections. Shear banding also resulted in a reduction in intensity of the rolling texture components and had a randomizing effect on the recrystallization texture of the Al layers. In both conditions, the Al(Sc) layers were resistant to recrystallization after extended annealing at 350 °C and produced a microstructure of recovered equiaxed grains ∼0.5–0.8 μm in diameter.