细颗粒钨粉团聚和消除方法的研究

Study on agglomeration and elimination methods of fine tungsten powder

细颗粒钨粉具有颗粒细小、活性高、比表面积大等特点,其分散性差,易产生团聚,粉末流动性差,松装密度低,严重影响钨粉后续球化结果。分析了细颗粒钨粉产生团聚的原因和团聚对钨粉球化结果产生的影响,并通过球磨实验解决了细颗粒钨粉团聚问题。结果表明：经过球磨处理后,钨粉D10、D50、D90粒径由球磨前的8.446、20.186、45.686μm降低至4.393、6.289、9.573μm左右,粒度明显下降,粒度分布明显变窄。在球磨作用下,大块团聚体被分散开来,钨粉大都呈单颗粒状态存在,颗粒分散状态良好。球料比4∶1（质量比）、球磨时间3 h、转速为100 r/min时,所得钨粉的分散状态最佳。

Fine tungsten powder has the characteristics of fine particles,high activity,high specific surface area,etc. Its dispersibility is poor,and it is easy to agglomerate,resulting in poor flowability and low loose density,which seriously affect the following spheroidization reslut of tungsten powder. The agglomeration causes of fine tungsten powder and the influence of agglomeration on spheroidization were discussed and summarized,and the agglomeration of fine tungsten powder was solved by ball milling experiment. After ball milling,the particle size and distribution of fine tungsten powder are decreased and narrowed,the values of D10,D50 and D90 are decreased from 8.446,20.186 and 45.686 μm to about 4.393,6.289 and 9.573 μm,respectively. The large agglomerates are dispersed,tungsten powder is mostly in a single particle state,and the particles are well dispersed. The optimum process parameters are obtained as the ball-to-material ratio is 4∶1（mass ratio）,the ball milling time is 3 h,and the rotating speed is 100 r/min.