Combined Influence of Severe Plastic Deformation and Cold Rolling on Mechanical Properties of Al–Mg2Si Alloys

Abstract

This article describes the strength properties and microstructure of Al–Mg–Si alloys positioned on a quasi-binary Al–Mg₂Si cross section and doped with minor amounts of scandium with zirconium and scandium with hafnium; after quenching, these alloys were exposed to severe plastic deformation and cold rolling with subsequent aging. It was demonstrated that, in the alloys with 1.4% Mg₂Si and doped with Sc + Zr and Sc + Hf after equal channel angular extrusion and subsequent cold rolling, the highest strength was that of the alloys doped with scandium with zirconium. The lowest strength was that of the alloys both doped and not doped with scandium, zirconium, and hafnium after equal channel angular extrusion. It has been established that cold rolling of quenched alloys and alloys after equal channel angular extrusion improves strength properties after aging at 170°C in comparison with those aged at the same temperature only after equal channel angular extrusion or only after cold rolling. Analysis of the microstructure has shown that strengthening of the alloys is attributed to slight distortion of the crystalline lattice of aluminum solid solution which is achieved by cold rolling of the alloys aged after equal channel angular extrusion.