Correlation of thermo-mechanical properties with microstructure in commercial pure Cu and Cu–Zn alloys studied by positron annihilation

Isochronal annealing of cold-rolled commercial pure copper (99.97%), Cu–28% Zn, and Cu–32% Zn has been investigated between room temperature and 1173 K. The annealing stages have been identified as recovery, partial recrystallization, complete recrystallization and grain growth using Vickers microhardness, positron annihilation lifetime, and doppler broadening of annihilation radiation measurements. The retardation of complete recovery in Cu–Zn alloys is due to the presence of vacancy–Zn complexes.