THE SYNTHESIS OF ULTRAFINE SIC POWDER BY THE MICROWAVE-HEATING TECHNIQUE

Ultrafine powders of silicon carbide synthesized by microwave and conv entional heating are described. Silicon carbide powders with diameters in the nanometer range were formed by reducing SiO2 with various form s of carbon in a nitrogen atmosphere. Ultrafine SiO2 powder, phenolfor maldehyde resin and ultrafine carbon black were used as starting mater ials. The properties of the powders were determined by means of X-ray diffraction, TEM, etc. The results showed that the technique and condi tions for preparing samples, as well as the temperature and type of he ating, had obvious effects on the powders characteristics.