微空心阴极维持放电的实验研究

摘要

Based on micro-hollow cathode discharge (MHCD) as a plasma cathode, a second anode was added to the device for　obtaining large volume and uniform plasma at high pressure. The discharge producing condition of MCSD was investigated in the　experiments. And the rotational structures of the N2 first positive bands were analyzed with traces of nitrogen added in argon for　the measurements of the gas temperature in the MCSD plume. The experimental results show that when the current of the plasma cathode exceeds the threshold, the large volume stable plasma is generated. The gas temperature in the plume is increased a　little with increasing the current (0. 5～4 mA) and is about 500 K at the pressure of 50 Torr.%为在高气压下形成大体积均匀等离子体,将微空心阴极放电(MHCD)作为等离子体阴极,引入另一阳极而设计为微空心阴极维持放电(MCSD)的发生装置.实验研究了MCSD的产生放电条件,通过在氩气中添加少量氮气,分析氮分子第一正带系发射光谱的方法测量了MCSD中羽流区不同位置的气体温度.研究表明,当等离子体阴极电流增加到一个临界值(约为0.5～1 mA)以后,在等离子体阴极与诱导阳极之间才会出现大体积辉光放电,羽流区气体温度在实验条件下约为500 K.MCSD减缓了辉光向弧光的转变,在高气压下可产生稳定的大体积辉光放电.