高压电场中金属丝段电爆产物的形成

Production of Segmented Metal Wire Electrical Explosion in the High Voltage Field

应用金属丝段与电极非接触电爆设备，通过改变电场电压和电极间距进行系列电爆金属铜丝试验，对爆炸后产物进行分离称量，并利用显微镜观察各种产物的形貌特点，结果表明，丝段进入高压电场后，通过丝端部与电极之间的气体放电将大电流导入而发生电爆。等离子体旁路作用使湮没在等离子体内部一部分或整根金属丝段不发生电爆残留下来。电极间距较长时，释放在金属丝段上的能量密度减小，不能够使整个金属丝段气化爆炸。适合制备超细粉的电极间距范围随电场电压的增加而扩大，对应电场电压4kV、5kV和6kV时，适合制备超细粉的电极间距范围分别为23．3—25．2mm、22．7—27．3mm和22．7—58．6mm。

With variations of the voltages of electrical field and distance between electrodes, a series of experimental explosion of segmented metal wire was carried out. In the experimental setup , the segmented metal wire was ＇not contacted with electrodes. After the explosion, the ultra-fine powders and the residues were separated and weighed respectively and the topography feature of every product was observed by Microscope. The result showed that the breakdown between electrodes and tips of the segmented wire, provides the channels through which the current flow in the segmented wire for explosion to occur. It is evident that the segmented metal wire, around the point of air breakdown which is known as the shunting arc, do not explode in the same way as the rest of the wire. The energy density which was released on the metal wire decreased with the electrode span increasing,and then the energy density was not enough to vaporize metal wire. The best process condition of wire electrical explosion is that, for the given field voltages of 4 kV, 5 kV and 6 kV, the corresponding ranges of electrode span are 23.3-25.2 mm,22.7-27.3 mm and 22.7-58.6 mm, respectively. The range of suiting the powder preparation was extended with the voltage increasing.