Effect of Scandium and Other Transition Metals on the Recrystallization of Al–Mg2Si Alloys after Equal-Channel Angular Pressing

Abstract

Optical microscopy and hardness measurements are used to study the influence of (Sc + Zr) and (Sc + Hf) transition metal additions and severe plastic deformation by equal-channel angular pressing (ECAP) on the temperature of recrystallization in aluminum Al–Mg2Si alloys. Recovery is revealed to take place in the Al–Mg2Si alloys in the temperature range 200–600°C. Joint scandium and hafnium alloying of the ECAP-deformed alloys weakens softening during recrystallization due to the formation of a structure with grains smaller than those in the structure formed in the alloys free from transition metals.