The role of shear banding on the fatigue ductility of ultrafine-grained aluminium

To study the effect of deformation mode used for grain refinement on the low-cycle-fatigue (LCF) behaviour of ultrafine-grained (UFG) materials, a commercially pure Al was subjected to cryorolling, and room temperature symmetric and asymmetric rolling. The LCF test was conducted under fully reversed total strain amplitude control. Despite its lower tensile ductility, the cryorolled Al had significantly higher fatigue ductility. This has been attributed to a higher density of shear bands in the cryorolled Al.