Fabrication of in situ Al2O3/Al composite via remelting

In the present work, in situ Al2O3/Al composite was produced via CuO/Al composite and subsequent remelting, and the chemical reaction evolution and the fractography were investigated by means of differential scanning calorimeter (DSC), X-ray diffraction (XRD), electron probe micro-analysis (EPMA) and scanning electron microscopy (SEM). The experimental results showed that Al2O3 could be successfully formed in situ by the addition of CuO to aluminum. The results also suggested that the fracture mechanism changed from interfacial debonding in copper oxide/Al composite to particle cracking in Al2O3/Al composite, which was largely attributed to interfacial bonding increased between in situ Al2O3 particle and Al. The Cu–O stability in the present processing was also discussed from the point view of thermodynamics.