丝直径和长度对电爆铜丝制备超细粉的影响

提出一种电爆金属丝制备超细粉的新方法,金属丝不与电极接触而是在高压电场中爆炸形成超细粉.研制试验装置,电爆不同直径和长度的铜丝,并获得超细粉末.在扫描电镜下观察粉末形貌,结果显示,粉末颗粒为圆球状,多数处于纳米级,且分散良好.采用对数正态分布算法分析粉末粒度分布.结果表明,粉末的粒度分布集中,平均粒径较小.进一步研究发现,铜丝直径越小,电爆制备的粉末中位径就越低、粒度分布越窄;电极间距一定时电爆长度适中的铜丝,可获得中位径小、粒度分布窄的纳米粉.

Influence of diameter and length of cupro-wire on preparation of ultra-fine powders by using wire electrical explosion

A novel method for preparing ultra-fine powders with electrical wire explosion was proposed,where the metallic wire could explode in high voltage electric field without contacting with electrodes to obtain ultrafine powders.An experimental device and a set of copper-wires with different diameters and lengths were developed,so that ultra-fine powders were successfully produced.The SEM images of the powder revealed that the particles of powder took spherical shape with high dispersibility,their sizes were prevalently of nanosize.The log-normal algorithm was applied to analyze the powders distribution,and the results indicated that most powders had low mean diameter and narrow distribution range of particle size.The further research showed that the diameter and length of copper-wire influenced markedly powders distribution.The mean diameter and distribution range of powders would be lower when the diameter of explosive wire decreased.In addition,well-distributed powders could be produced by exploding the wire with appropriate length under definite space length between the electrodes.