Preparation of SiC/BN nanocomposite powders by chemical processing

摘要

The silicon carbide (SiC)/BN nanocomposite powders that had the microstructure of micro-sized SiC particles coated with nano-sized BN particles were fabricated via a chemical reaction of boric acid and urea on the surface of SiC particles in a nitrogen gas. The results of X-ray diffraction analysis (XRD), transmission electron microscope (TEM), and selected area electron diffraction (SAED) showed that the coating layer was composed mainly of amorphous and nano-sized BN particles at the reaction temperature of 850 deg C. After reheating the composite powders at 1750 deg C in a nitrogen gas, the amorphous BN was transformed into h-BN.