Mono-tungsten carbide prodn. - from volatile tungsten cpd. and vapourised carbon source and calcination of solid prod. contg. di-tungsten carbide

摘要

WC prepn. process by vapour-phase reaction of a volatile W cpd., (I), with a vaporised C-source, (II), at 300-3000 (1500-2500 degrees C) in a reaction zone, takes place by introducing (I) and (II) to reaction zone in a quantity such as to supply =1C atom for each W atom; drawing off solid W carbide prod. contg. W2C as main component; and calcining the solid W carbide prod. at 500-1500 (800-1200 degrees C), pref. for 0.25-12 (1-4) hrs., until W carbide prod. contains WC as main component. WC is used for prepn. of sinter WC, suitable for prodn. of cutting tools and abrasives. Prod. contains 5% W2C and may consist of finely divided WC havving particle size 0.1-0.5 mu. (I) may be a W halide, pref. WCl. (II) may be 1-12C hydrocarbons and/or 1-8C halohydrocarbons, esp. CHCl2CH2Cl.