Crystal growth of tungsten during hydrogen reduction of tungsten ozide at high temperature

摘要：

Crystal growth of tungsten during hydrogen reduction of tungsten oxide (WO3) to prepare coarse grain tungsten powder at high temperature (950 ℃) was studied. The phase composition and morphologies of products were investigated by means of XRD and SEM. The results show that the reduction sequence of hydrogen reduction of WO3 is WO3→WO2.9→W18O49→WO2 →W. The step of WO2→W is the critical step which determines the grain size of tungsten powder. The partial pressure (pH2O//pH2) of H2O within powder layer shows strong effect on the nucleation and grain growth of tungsten. By increasing the ph2o/Ph2 within powder layer, well-developed coarse grain tungsten powder with particle size above 15 μm is obtained. After carburizing, the powder can be used to produce ultra-coarse grain cemented carbide with grain size above 5 μm.

关键词： coarse grain tungsten powder hydrogen reduction of tungsten ozide crystal growth partial pressure

作者: WU Xiang-wei YI Dan-qing LUO Jing-song LU Bi-zhi XIE Chen-hui PI Zhi-ming HU Mao-zhong XU Tao WU Guo-gen YU Zhi-ming

作者单位: School of Materials Science and Engineering, Central South University, Changsha 410083, China Zhuzho School of Materials Science and Engineering, Central South University,Changsha 410083, China Zhuzhou Cemented Carbide Group Corp.Ltd., Zhuzhou 412000, China Zhuzhou Cemented Carbide Group Corp.Ltd.,Zhuzhou 412000, China Zhuzhou Cemented Carbide Group Corp. Ltd., Zhuzhou 412000, China School of Materials Science and Engineering, Central South University, Changsha 410083, China

会议类型: 国际会议

会议名称: 2009 Frontier Symposium of China Postductors on Materrials Science(2009年中国博士后材料科学前言论坛)

会议地点: 长沙

会议语种:英文

页码: 785-789

在线出版日期: 2009-11-22（万方平台首次上网日期，不代表论文的发表时间）