Jet milling has been applied into many industries as an advanced technology in powder preparation. While the surface static electrons produced by friction between particles during grinding process and the strong adsorption property for particle size reduction will lead to agglomeration of the particles thus prepared,which offsets the advantages of micropowder to certain.Based on the Coulomb principle which states that particles car-rying charges of the same sign repel each other,the electrostatic dispersion was an innovative methodology which employs electrostatic effect to annihilate agglomeration,the more the charges carried by powder is,the better the dispersion of it was.In this paper,we proposed a new method to prepare micropowder with a combi-nation of j et milling and electrostatic dispersion techniques,and the charge-to-mass ratios of talc powders with different sizes have been measured experimentally.The results indicate that when the air pressure was lower, the charge-to-mass ratio of the talc with larger size increases with the increase of charging voltage,while it rea-ches the maximum at 40 kV when the air pressure was larger.But the charge-to-mass ratio of the talc with smaller size increases with the increase of charging voltage all the time.Besides,the charge-to-mass ratio of talc decreases with the increase of air pressure when the charging voltage was fixed,and the charging property of powder with smaller size was better compare to larger size under the same charging condition.%气流粉碎作为超微粉体制备的一种先进技术被广泛运用在工业生产中，然而气流粉碎过程中颗粒间剧烈摩擦所形成的表面静电以及由于颗粒粒径减小所带来的强吸附性能，都将引起粉碎后的颗粒发生再次团聚，从而导致超微粉体的优良特性劣化。静电分散作为一种新型的物理分散法，通过使粉体颗粒在电晕电场中荷以同一极性的电荷，利用颗粒之间的库仑斥力进行分散，荷电量越大则粉体的分散性越好。以不同粒径的滑石粉为研究对象，对气流粉碎/静电分散相结合方法中粉体的荷电特性进行了实验研究。研究结果表明，平均粒径较大粉体的荷质比在较低气压下随着荷电电压的升高而增大，当气压较高时在40 kV下存在一峰值；而平均粒径较小粉体的荷质比均随着荷电电压的升高而增大。荷电电压恒定时滑石粉荷质比随着气流压强的增大而减小。相同荷电条件下粒径较小的粉体颗粒的荷电性能优于粒径较大颗粒。
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