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【Chinatungsten Online News Net- Tungsten News】

The ultrafine tungsten carbide powder is actually the carbonization of ultrafine tungsten powder. the influence factors of particle size of tungsten carbide powder is investigated, the results show that the most important factor is the particle size and particle size distribution of tungsten powder. As the carbonization process is realized by the reaction with carbonaceous gases on the surface of tungsten particles and by solid state diffusion of carbon black, the effect of carbonization temperature, carboni-zation time and carbon content of mixtures on particle size of tungsten carbide powder are relatively less. The optimal process condition for producing ultrafine tungsten carbide powder is established by experimental verification, and ultrafine tungsten carbide powder is produced.  The ultrafine powders prepared are highly agglomerated and with broad particle size distribution. Experiments show that the technology of air stream classifying has significant effect on increase of the fineness and uniformity of ultrafine powders. Superfine pulverizing grader has high production efficiency and low energy consumption, and yet is easy to operate and control. Air stream pulverizing and grading produces ultrafine powder with less agglomeration and narrow particle size distribution. Superfine pulverizing grader significantly improves production efficiency of ultrafine powders.