Fabrication and characterization of supersaturated Al-Mg alloys by severe plastic deformation and their mechanical properties

Excess amount of Mg was intentionally added to fabricate supersaturated ultra-fine grained Al-Mg alloy by high pressure torsion (HPT). Their microstructures and mechanical properties were examined by X-ray diffraction (XRD) analysis, transmission electron microscopy (TEM) and Vickers microhardness test. It was confirmed that the minimum grain size reached ̃40 nm and maximum microhardness 292 Hv at the Mg content with 30mass%. Further increase of the amount of Mg resulted the formation of ß-Al₃Mg₂ and decrease of microhardness.