Recrystallization behavior of Al2O3/Cu composite produced by internal oxidation

Using Cu2O as oxidizer, Al2O3 dispersion strengthened copper composite was produced by Cu-Al alloy powder internal oxidation and followed by powder metallurgy. The samples with the different contents of Al2O3 were cold drawn at the different rates of the deformation, then were annealed at 700 degrees C-1050 degrees C for 1 h in nitrogen atmosphere. The variation of the hardness with the annealing temperature was studied, and the microstructures of the samples were observed. The results show that the nano-alumina particles are homogeneously distributed in Cu-matrix, the hardness of the samples annealed at 900 degrees C for 1 h can be up to 87% of that at the room temperature and their recrystallization temperature can reach 1000 degrees C. The results also show that increasing of the alumina content or cold deformation rate will increase the hardness of the produced Al2O3/Cu composite but has little effects on softening and recrystallization temperature over the experimental range.