感应等离子体工艺对制备致密球形钼粉的影响

Effect of induction plasma process on preparation of dense spherical molybdenum powder

研究了原料钼粉携带气体流量和钼粉加料速率对感应等离子球化钼粉形貌和粒度的影响。球化前后钼粉的微观形貌用扫描电镜（SEM）观测,粉体物相用X射线衍射仪（XRD）分析,等离子体处理前后钼粉的松装密度和振实密度分别用斯科特容量计和振实密度仪检测。结果表明,等离子体处理后产品仍为纯金属钼粉,形状由不规则变为球形,颗粒平均粒径由原料的40~70μm减小至35~60μm,振实密度由2.5 g/cm3提高到5.8 g/cm3。制备球形钼粉最佳工艺参数为：加料速率45 g/min,携带气体流量0.6 m3/h。感应等离子体是制备高纯致密球形钼粉的有效技术。

Effects of the carrier gas flowing rate and molybdenum powder feeding rate on the shape and size of products were studied. The morphology of molybdenum powder was observed by high resolution scanning electron microscopy（ SEM）. The powder phase was analyzed by X-ray diffraction（ XRD）. The tap density and apparent density of molybdenum powder were investigated by Hall flow meter and Scott Volumeter,respectively. The results show that pure spherical molybdenum powder can be obtained from irregular shape powder,and the tap density is much enhanced after plasma processing. The average size is reduced from 40-70 μm to 35-60 μm and the tap density is raised from2. 5 g / cm^3 to 5. 8 g / cm^3. At the same time,the optimum process parameters to prepare spherical molybdenum powders are as follows： the powder feeding rate is 45 g / min,and the carrier gas rate is 0. 6 m3/ h. Therefore induction plasma is a promising method for preparing spherical powders with high density and high purity.