A super-high temperature furnace was developed to fabricate spheroidal cast tungsten carbide powder with excellent flowability and fine feathery structure in a large scale. Optical microscope and scanning electron microscope were taken to characterize the morphology and microstructure of cast tungsten carbide powder. X-ray diffractometry was used to analyze the phase composition of powders involved. It is found that the carbon potential in the furnace and feeding speed play an important role on the microstructure, morphology and properties of the spheroidal cast tungsten carbide powder. As carbon potential is between 0.3% and 0.9% in the furnace, cast tungsten carbide powder with hardness over 2800(HV0.5), flowability over 7.1s/50g and tap density over 10.3g/cm3 is obtained. 

Hard surface technology is of great significance to promote sustainable economic development and build an economical society. Forming hard wear layer on metal/alloy surface with hard surface technology can significantly improve workpiece life and save resources. Due to its high hardness, high abrasion resistance and corrosion resistance, tungsten carbide casting is one of the most widely used hard surface materials. The surface morphology, microstructure and particle size of cast tungsten carbide have a decisive effect on its application. The spheroidal _ fast cooling treatment of traditional cast tungsten carbide powder can significantly improve the toughness of hard surface materials containing cast tungsten carbide, and achieve the best combination of high abrasion resistance and high toughness of hard surface materials. At present, the most representative company in the world that can prepare spherical casting tungsten carbide powder on a large scale is Tekna company of Canada. The company USES high temperature plasma technology to prepare spherical casting tungsten carbide powder. Because of the large flow of Ar gas as plasma carrier and protective atmosphere, the production cost is relatively high. The preparation of spherical casting tungsten carbide powder has been reported at home and abroad. The preparation methods of spherical casting tungsten carbide powder are mainly divided into three categories, namely, plasma high-temperature technology represented by Tekna company. Liquid direct atomization forming technology (CN1486806), represented by hunan dinglixin material engineering center co., LTD and zigong cemented carbide co., LTD. CN1488463, atomization forming method for producing ball casting tungsten carbide powder, 2004.04.14); High temperature arc melting centrifugal fast cooling technology represented by zhuzhou huayang technology co., LTD and Woka Schweisstechnik GmbH (CN2714579, a spherical amorphous material preparation equipment, 2005.08.03; American patent 5089182, Process of manufacturing cast tungsten carbide spheres, 1992.02. 1 The preparation method of spherical casting tungsten carbide has some problems, such as large gas consumption, poor stability of spherical degree control due to strong impact of airflow in the pellet forming process. In addition, the above technologies also have problems such as wide particle size distribution of spheroidized powder, relatively poor controllability of particle size distribution, poor stability of preparation process, low production capacity and high maintenance cost of equipment.

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