Microstructure and Interfaces of Al₂O₃/SiC Nanocomposite

Abstract

Al₂O₃/SiC nanocomposites were successfully prepared by the conventional powder metallurgical technique. The microstructures of Al₂O₃/SiC nanocomposites were mainly investigated by transmission electron microscopy(TEM). TEM observaions indicated that the Al₂O₃ matrix grains were essentially equiaxed with the average gain size of 1 to 2 μm and the SiC particles were predominantly dispersed within Al₂O₃ matrix grains. Al₂O₃-SiC interfaces in Al₂O₃ grains containing intragranular SiC were generally observed with faceting but in part with sphere by high resolution electron microscopy(HREM). HREM observations also revealed that the Al₂O₃ and SiC grains in Al₂O₃/SiC nanocomposites made direct interfaces without any reacting phases.