HYPERFINE POWDER OF SIC, METHOD AND APPARATUS FOR MANUFACTURING IT

摘要

PURPOSE:To manufacture inexpensively hyperfine powder of SiC having a simple composition and a uniform particle size by subjecting SiO vapor to adiabatic expansion in an atmosphere of nitrogen or the like and by heat treating the resulting hyperfine powder of amorphous SiO in a reducing and carbonizing atmosphere. CONSTITUTION:A reaction chamber 1 and a capturing chamber 34 connected by a duct 21 are evacuated with a vacuum pump 44, and a starting material contg. almost equimolecular amounts of inexpensive SiO2 and Si or C is charged into the chamber 1 heated to =about 1,300 deg.C with a heating element 2 from a storage vessel 11 to generate SiO vapor. The vapor is injected into the chamber 34 from a nozzle 22 through the duct 21 at the kinetic velocity of molecular movement or above, and it is rapidly cooled by adiabatic expansion to form hyperfine powder of amorphous SiO. At this time, nitrogen or ammonia is previously fed to the chamber 34 through a gas distribution ring 29. Oxygen may be fed up to a prescribed reduced pressure. The SiO powder is heat treated in a reducing and carbonizing atmosphere of C2H2 or the like in a heat treatment furnace 60 to obtain hyperfine powder of SiC having =1mum particle size. The SiC is amorphous SiC, beta type SiC or alpha type SiC in accordance with the treatment temp.