Al–Zn alloys having diferent Zn contents of 2, 5, 10 and 30 wt% were processed by high-pressure torsion (HPT) to produce ultrafne-grained (UFG) materials. Microstructural features of these UFG Al–Zn alloys were investigated using depth-sensing indentations, focused ion beam (FIB), scanning electron microscopy (SEM) and diferential scanning calorimetry (DSC). Emphasis was placed on the microstructure evolution of the alloys with diferent Zn-concentration which demonstrated substantially diferent mechanical behavior, exhibiting superductility with increasing Zn content. It was shown that
in every case, HPT resulted decomposition in the microstructure, but there is a signifcant diference between the microstructures of alloys with low and high Zn content. Based on the microstructural observations, a scenario is proposed about that how the decomposed microstructure developed during HPT process in low- and high Zn-containing Al–Zn alloys, infuencing their mechanical behavior.