燃烧合成氮化硅粉体的超细粉碎

采用燃烧合成氮化硅原始粉料,用球磨的方法进行颗粒超细粉碎,探讨了球磨时间与粉料粒度的关系。结果表明,随着研磨时间的增长,平均粒径减小,但研磨时间的延长到一定时,粒径基本不再减小。该粉料经过24h的球磨后,其平均粒径可降低一个量级,由微米级细化到亚微米级0.5μm左右。粒度分布由原来双峰分布变成了狭窄的单峰分布,颗粒细而均匀。测试了粉体超细粉碎前后的粒度及比表面积,并对其形貌进行了显微形貌观察,讨论了超细过程中的一些现象,对不同球磨机的研磨效果进行了对比。

Ultrafine Comminution of Si_3N_4Prepared by Self-propagating Combustion Synthesis

Si3N4 powder made from self-propagating combustion synthesis (SHS) was ultrafinely ground by attrition mill. The relationship between grinding time and particle size were investigated. The experimental results showed that at the beginning with grinding time increased, the mean particle size decreased gradually. After a certain grinding time, the particle size kept even although grinding time increasing. After 24 hours grinding, the particle size of raw materials of 1~2 microns broken down into sub-micron sc...