Gradual softening of Al–Zn alloys during high-pressure torsion

Evolution of the microstructure and mechanical properties of Al–30 wt.% Zn alloy after the severe plastic deformation (SPD) by the high-pressure torsion has been investigated in detail in dependence on the increasing deformation degree. SPD leads to the gradual grain refinement and decomposition of the Al-based supersaturated solid solution. Measurements of the microhardness reveal a successive softening of the alloy with the increased deformation degree.