Microstructure characterization of a pressureless infiltrating oxidized SiCp preform by A1-8Mg

The microstructure of a pressureless infiltrating 55vo1% oxidized SiC preform by Al-8Mg alloy was characterized by transmission electron microscopy (TEM), high resolution TEM (HRTEM), field emission scanning electron microscopy (FE-SEM), and X-my diffraction.The TEM image of the interface between Al and SiC shows that the surface of SiC is covered by a rough nanocrystal layer of MgAl2O4,Al2O3, and Si, produced by the interracial reaction of Al, Mg, and SiO2 on the surface of SiC. The Al-SiC interface is also examined by HRTEM to be better understood how MgAl2O4 and Al2O3 ale produced Dendritic Al2O3 crystals are embedded in the pores of the composite generated from the mutual bonding of SiO2 on the surface of SiC. Columnar AlN crystals of about 250 nm in length are bunched vertically on the SiC particle surface.