纳米钨粉粒度分布的表征研究

采用X射线小角散射法（SAXS）和光子相关谱法（PCS）测试了纳米钨（W）粉的粒度分布。结果表明,采用SAXS测试出的纳米W粉的粒度分布与透射电镜观察和比表面积法测试结果十分接近,能较为准确地表征纳米W粉的一次颗粒的粒度分布;但为了得到可信的结果,所选择的X射线衍射仪的最小可测试角必须足够小。PCS法测试的纳米W粉的粒度随分散条件的变化而变化,所提供的最佳分散条件可用于测定二次颗粒的粒度分布。

THE CHARACTERIZATION OF PARTICLE SIZE DISTRIBUTION IN NANO-SCALE TUNGSTEN POWDERS

Both small angle X-ray scattering(SAXS) and photon correlation spectroscopy(PCS) were used to characterize the particle size distribution of nanoscale tungsten powders.Through the comparison of the SAXS results with TEM and BET results,SAXS was proved to be an effective method to characterize the primary particle size distribution of nano-scale tungsten powders.However,proper X-ray diffraction with minimum measuring angle which is small enough should be chosen in order to obtain reliable size distribution of nano-scale powders.The size distribution of nano-scale tungsten powders measured by PCS was changed with the dispersion condition.According to the dispersion condition recommended in this paper,PCS could be used to characterize the size distribution of secondary particles.