砷对紫钨制备及碳化过程的影响  

Effect of Arsenic on the Preparation and Carbonization Process of Violet Tungsten Oxide

作　　者：易志强 涂丹 谭敦强[1] 王晓茹 何文[1] 邝海[1] 邹志航 邓冲[1] YI Zhi-qiang;TU Dan;TAN Dun-qiang;WANG Xiao-ru;HE Wen;KUANG Hai;ZOU Zhi-hang;DENG Chong(School of Materials Science and Engineering,Nanchang University,Nanchang 330031,China)

机构地区：[1]南昌大学材料科学与工程学院

出　　处：《稀有金属与硬质合金》2019年第3期25-30,共6页Rare Metals and Cemented Carbides

基　　金：国家自然科学基金(51564036,50904035);国家高技术研究发展计划(863计划)(2012AA061902);国家科技支撑计划(2011BAC10B04);南昌大学研究生创新专项资金项目(CX2017008)

摘　　要：砷(As)是白钨矿中常见的杂质元素,通常在冶金过程中需对其进行除杂处理,而As对后续钨产品的影响尚不清楚。以仲钨酸铵(APT)和As单质为原料制备As质量含量为1%的APT-As复合粉末,经煅烧和碳化,分别制备出含As的紫钨(W18O49-As)及碳化钨(WC-As)。采用X射线衍射仪、扫描电镜、高分辨透射电镜和差示扫描量热仪对W18O49-As及WC-As的形貌及结构进行分析。分析结果表明:As元素主要以W2O3(AsO4)2第二相的形式存在于棒条状W18O49-As的表面,易使棒条状W18O49-As发生断裂;W18O49-As还原和碳化反应起始温度比不含As的W18O49低;W2O3(AsO4)2第二相分布于W18O49之间,阻碍W18O49碳化过程中物质的迁移扩散,从而抑制细小WC颗粒的聚集长大,得到均匀性好的WC-As粉末。Arsenic (As) is a common impurity element in scheelite,and needs to be removed in the metallurgical process. However, the effect of arsenic on the subsequent tungsten products is not clear. APT-As composite powders with As mass content of 1% was prepared by using ammonium tungstate and As element as raw materials. After the treatment of calcination and carbonization, violet tungsten oxide(W18O49-As) and tungsten carbide (WC-As) containing arsenic were obtained, respectively.X-ray diffractometer, scanning electron microscope, high-resolution transmission electron microscope and differential scanning calorimeter were used to analyse the morphology and structure of W18O49-As and WC-As. The results show that As element mainly exists in the surface of the bar W18O49-As in the form of W2O3 (AsO4)2 phase,making bar W18O49-As easily break. The initial reaction temperatures of reduction and carbonization of W18O49-As are lower than those of W18O49. The phase of W2O3 (AsO4)2 is distributed between W18O49 powders,hindering substance migration and diffusion in the process of W18O49 carbonization and inhibiting aggregation and growth of fine WC particles,so the uniform WC-As powders are obtained.

关 键 词：砷 紫钨 碳化钨 均匀性 

分 类 号：TG146.411[一般工业技术—材料科学与工程]