The tungsten powder produced by tungsten hexachloride

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The tungsten powder produced by tungsten hexachloride mainly includes using tugsten waste as raw materials and directly applying the chlorination process and hydrogen reduction in the reactor which has 20-25mm of tube diameter and 60mm of the middle expanding diameter. In the reduction process, firstly put the tungsten waste into the middle expanding area of the inner pipe and keep the charge amount as 1-1.5 kg each time. Meanwhile, the inside and outside pipes are both heated with the hydrogen circulation. The heat should be preserved when the temperature rises to 800 degrees Celsius in the chloride section in the reactor, while in the reduction section, the temperature should be heated to 1000 degrees Celsius. When the temperature is promoted to the required ones, preserve the heat in 1h so as to effectively remove the moisture in the reactor surface and raw materials and also remove the oxidation film existed on the raw material surface by hydrogen reduction. Under the hydrogen circulation condition of outside pipe, stop infusing hydrogen in the inside pipe and begin to infuse the chlorine so as to drive hydrogen in the inside pipe. When the hydrogen in the pipe and chlorine both pass into the inside pipe, the chlorine will react with raw material tungsten immediately and generate the mixture of gaseous hexachloride tungsten as well as pentachloride tungsten which will flow into outside pipe of reduction section and encounter with preheated outside pipe hydrogen, with which the gas-phase reaction will be occurred and thus generate tungsten metal powder.

The tungsten powder made by hexachloride tungsten has superfine particles, neat particle shape, narrow particle size distribution, high chemical purity and thermoelectricity having stable grains, which cannot be matched by other technology. Besides, the finished products produced by hexachloride tungsten will provide good raw material for the cemented carbides and will also find its important usage in the synthetic diamond core bits, high specific gravity alloys, tungsten materials, electrical contacts, filters and other fields.