Microstructural evolution during recovery in Al-2.5%Mg alloys

Microstructural evolution in Al-2.5%Mg alloys with various Fe content deformed by cold rolling [ε̄=0.1-3] and recovered during static annealing (160 and 220°C) was studied experimentally using the transmission electron microscopy techniques. Detailed investigations of the dislocation structures at small prestrains reveal a channel-like planar arrangement which does not show significant subgrain growth during annealing, whereas subgrain structures formed at higher prestrains lead to the onset of recrystallization when annealed. The microstructural evolution is discussed in relationship with the mechanical properties (yield stress) of the alloys.