Microstructure and properties of Cu–Mg alloy treated by internal oxidation

Abstract

ABSTRACTA Cu–0.24Mg alloy bar was treated by internal oxidation using Cu2O as an oxidiser at 1123–1273 K for 10 h. The thermodynamic diagram for oxidation of a Cu–Mg alloy was confirmed by the critical oxygen pressure. The results show that the thickness of the MgO/Cu layer and the electrical conductivity of the Cu–0.24Mg alloy increase with increasing internal oxidation temperature, whereas the average hardness of the MgO/Cu layer initially increases and subsequently decreases. Examination of the microstructure of the MgO/Cu layer revealed that Mg precipitation in the form of MgO particles and their uniform dispersion in the Cu matrix were the primary reasons for increases in the comprehensive properties of the Cu–Mg alloy treated by internal oxidation.