用流态化工艺制备WC-Co粉末

PREPARATION OF WC-Co POWDER BY THE FLUIDIZATION TECHNOLOGY

用偏钨酸铵和硝酸钴原料喷雾干燥制成ＣｏＷＯ４／ＷＯ３复合粉末，用流态化反应炉使之在Ｈ２和ＣＨ４／Ｈ２气相中连续。原碳化成ＷＣ－Ｃｏ粉末，着重研究了不同还原碳化工艺及其产物的形成机理。测试结果表明，所制ＣＯＷＯ４／ＷＯ３复合粉末呈均气球形的非晶和微晶混合态，ＷＣ－Ｃｏ粉末的晶粒细小均匀、相纯度高，适于制备超细晶粒的ＷＣ－Ｃｏ硬质合金。

The ammonium metatungstate and cobalt nitrate aqueous solution were spray- dried toCoWO4/WO3 mixed oxide. WC-Co were prepared continuously by H2 reducing and CH4/H2 carbonizingthe precursor powder in a fluldized-bed reactor. The different reduction/carburization processes andthe formation mechanism of the powder were studied. The results show that CoWO4/WO3 mixed oxidewas homogeneous and mixed spherical amorphous- microcrystalline aggregate. The WC-Co powderas-produced was pure. uniform and suited to be manufactured superfine-grain cemented carbide.Keywrods: WC-Co, fluidization, continuous reduction carburisation process, superfine-grain ce-mented carbide