Deformation-induced small-angle scattering contrast in aluminium alloys

Small-angle neutron scattering experiments have been performed on a uniformly stretched specimen (uniform elongation 18.5%) of commercial thin-sheet wrought aluminium alloy AA6013 (Al-Mg-Si-Cu) aged at room temperature. Comparison with undeformed material revealed characteristic deformation-induced anisotropy of the two-dimensional scattering pattern, which can be interpreted as being due to deformation-induced arrangements of preferentially aligned dislocation segments. The effect of anisotropy is larger but of the same type as that of small-angle X-ray scattering patterns obtained from the crack-tip plastic zone of cracked specimens.