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超细晶粒的WC-Co硬质合金具有高硬度、高强度的性能,纳米晶WC-Co复合粉末的合成是制备该合金的首要前提工作,中国正努力保持和强化“钨钴液相复合—喷雾干燥—流态化连续还原碳化技木”在国际上的前沿优势。该技术将偏钨酸铵和水合硝酸钴以分子级水平混合,经喷雾干燥制备出CoWO_4/WO_3复合氧化物前驱体粉末,然后将前驱体粉末置于流态化反应炉中,在H_2/CH_4/CO_2/N_2气氛下经过连续的还原、碳化、调碳过程,得到无缺碳相的纳米晶WC-Co复合粉末。
The ultrafine-grained WC-Co cemented carbide has the properties of high hardness and high strength. The synthesis of nanocrystalline WC-Co composite powder is the first precondition for the preparation of this alloy. China is trying hard to maintain and strengthen the “tungsten-cobalt liquid phase composite - Spray drying - fluidized continuous reduction carbonization technology ”in the international frontier advantage. In this technology, ammonium metatungstate and cobalt nitrate hydrate are mixed at the molecular level to prepare CoWO_4 / WO_3 composite oxide precursor powder by spray drying, then the precursor powder is placed in a fluidized reaction furnace, / CO_2 / N_2 atmosphere after continuous reduction, carbonization, carbon adjustment process, to obtain a carbon-free phase of the nanocrystalline WC-Co composite powder.