Shear bands evolution in ultrafine-grained aluminium under cyclic loading

The microstructural response and deformation mechanisms under cyclic and monotonic loading were investigated in a commercially pure Al subjected to grain refinement by cryorolling. A fatigue dependent shear banding and grain coarsening was detected and it was shown that pre-existing shear bands induced by cryorolling play a vital role in this regard. A rapid initial cyclic softening dominated by activation of pre-existing shear bands is replaced by a more gradual cyclic softening dominated by grain coarsening within these shear bands.