The rapid development of high technology requires new materials with superior properties, and puts forward higher requirements for the hardness, strength and wear resistance of materials. Tungsten carbide base ultra fine cemented carbides have showed excellent mechanical properties, when WC spraying powder grain size decreases to 0.5 mu m, alloy shows excellent comprehensive performance, especially of ultrafine alloy treated by HIP, due to eliminate the residual pore in the alloy, the alloy properties (tensile strength) was further improved. There are many methods to prepare ultrafine tungsten carbide powder, but they can be divided into chemical method and mechanical method. Chemical methods mainly include spray heat transfer, organic salt thermal decomposition, one-step reduction carbonization, etc. The mechanical methods include high energy ball grinding, vibration ball grinding and mechanical alloying. Israeli g. r. graen-muginstein et al. obtained nanometer tungsten carbide powder with powder size of 0.6 m after 300h ball grinding, and dry grinding powder size was more uniform (5 ~ 10nm), while wet grinding powder size was wider (1 ~ 50nm). In this study, the submicron tungsten carbide powder was prepared by vibrating ball milling method.

Ultra-fine grain cemented carbide has high hardness and high strength, and is widely used in the manufacture of microdrill bits, dot matrix printer needles and precision tools for the drilling of integrated circuit boards. Ultrafine WC sprayingpowderis an important raw material for the preparation of ultrafine cemented carbide. At present, the reports of preparing nanometer, ultrafine tungsten carbide powder, or the way of the composite powder is more, there are mainly tungsten oxide reduction carbonization method (that is, the traditional process), directly carbonized tungsten oxide method, plasma chemistry carbonation method, halide tungsten carbide method, since the reducing amine salt, high frequency plasma method, gas solid instead should method, freeze drying, etc. These methods, the traditional process is simple and easy, reasonable, stable and reliable, large production capacity and advanced products of good quality, low cost and efficiency higher advantages, and is closely related with tungsten carbide production in our country,whichis a kind of conform to China's national conditions, more province industrial production method, literature, points out that the traditional process made BET size is less than 0.2 microns ultrafine tungsten carbide powder as the U.S. DOW company is the quality of the production of the tungsten carbide powder. However, other methods still have disadvantages such as complicated process, high production cost, low efficiency and many impurities, which are suitable for industrial scale production.

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