APPLICATION OF POSITRON-ANNIHILATION SPECTROSCOPY TO STURDY RECOVERY AND RECRYSTALLIZATION OF COMMERCIAL PURE AL AND AL-1WT-PERCENT MN ALLOYS

Isochronal annealing of cold worked commercial pure aluminum (99.5 %) and Al-1wt % Mn alloys was demonstrated between room temperature and 8 23 Ii. The stages of recovery and recrystallization were studied using microhardness and positron annihilation lifetime measurements. A posi tive correlation was established between the variation of the intensit y of long lived component and Vickers microhardness with annealing tem perature during the two stages of recovery, which were identified in b oth aluminum and Al(Mn). The retardation of the recovery stages and re crystallization in AI(Mn) alloys is interpreted in terms of precipitat ion of aluminum-manganese particles as well as manganese-vacancy inter action.