Synthesis of high-purity ultrafine tungsten and tungsten carbide powders  

高纯超细钨和碳化钨粉体的制备

作　　者：Kai-fei WANG Guo-hua ZHANG 王凯飞;张国华(北京科技大学钢铁冶金新技术国家重点实验室,北京100083)

机构地区：[1]State Key Laboratory of Advanced Metallurgy,University of Science and Technology Beijing,Beijing 100083,China

出　　处：《Transactions of Nonferrous Metals Society of China》2020年第6期1697-1706,共10页中国有色金属学报（英文版）

基　　金：Project(51725401)supported by the National Natural Science Foundation of China。

摘　　要：High-purity ultrafine W or WC powder was prepared via a two-step process composed of the carbothermic pre-reduction of WO2.9 and the following deep reduction with H2 or carbonization with CH4+H2 mixed gases. The effects of C/WO2.9 molar ratio and temperature on phase composition, morphology, particle size, and impurity content of products were investigated. The results revealed that when the C/WO2.9ratio was in the range from 2.1:1 to 2.5:1, the carbothermic pre-reduction products consisted of W and a small amount of WO2. With changing C/WO2.9 ratio from 2.1:1 to 2.5:1, the particle sizes were gradually decreased. In order to prepare ultrafine W or WC powder, a relatively high C/WO2.9 ratio and a lower reaction temperature at this stage were preferred. After the second reaction, the final products of ultrafine W and WC powders with a high purity could be obtained, respectively.提出一种两步法制备高纯度W或WC粉体的工艺,该工艺包括碳热预还原WO2.9,以及后续的对还原产物进行H2还原或CH4+H2混合气体碳化。研究C/WO2.9摩尔比和反应温度对不同阶段产物的相组成、形貌、粒径及杂质含量的影响。结果表明,当C/WO2.9摩尔比为2.1:1-2.5:1时,碳热预还原产物的物相由W和少量WO2组成。随着C/WO2.9摩尔比从2.1:1增加到2.5:1,碳热预还原产物的粒径逐渐减小。因此,采用相对较高的C/WO2.9摩尔比和较低的反应温度有利于获得超细W或WC粉体。经过第二阶段的反应,可以制备高纯度W粉和WC粉。

关 键 词：carbothermic pre-reduction CARBONIZATION TUNGSTEN tungsten carbide 

分 类 号：TF841.1[冶金工程—有色金属冶金] TQ136.13[化学工程—无机化工]