太赫兹科学与电子信息学报, 2019, 17 (1): 174, 网络出版: 2019-04-07
金属表面形貌对真空击穿阈值的影响
Influence of metal surface morphology on the threshold of vacuum breakdown
场致爆炸电子发射 表面粗糙度 真空击穿阈值 field-induced explosive electron emission surface roughness vacuum breakdown threshold
摘要
探索提高真空击穿阈值的方法,对脉冲功率技术的发展和应用具有重要意义。在金属表面电子发射理论分析的基础上,采用有限元法计算电极表面电场随二极管电压的变化规律,设计实验系统,并开展实验研究。实验对比钛合金TC4阴极在不同表面粗糙度下真空击穿阈值,实验表明,当阴极表面粗糙度(轮廓最大高度Rz)分别为26.13?m,10.41?m,6.75?m,1.12?m,0.13?m时,击穿阈值分别为306?kV/cm,345?kV/cm,358?kV/cm,392?kV/cm,428?kV/cm。当Rz由26.13?m减小至0.13?m时,击穿阈值提高39%。金属表面击穿阈值随Rz减小而提高,减小金属表面的Rz,是提高真空击穿阈值的有效方法。
Abstract
It is important for the development and application of pulsed power technology to explore the way to improve vacuum breakdown threshold. On the basis of metal surface electron emission theory, the change law of electrode surface field with diode voltage is analyzed by finite element method. The experimental system is designed and the research is carried out. The experiment compares the TC4 cathodes’ vacuum breakdown thresholds under different surface roughness(Rz). The experimental results demonstrate that the surface roughness of cathodes is 26.13 ?m, 10.41 ?m, 6.75 ?m, 1.12 ?m and 0.13 ?m; and the breakdown threshold is 306 kV/cm, 345 kV/cm, 358 kV/cm, 392 kV/cm and 428 kV/cm respectively. When the Rz goes from 26.13 ?m to 0.13 ?m, the breakdown threshold is increased by 39%. The metal surface breakdown threshold increases with the decreasing of Rz. Reducing the Rz of metal surface is an effective way to improve the vacuum breakdown threshold.
胡祥刚, 宋玮, 向导, 朱晓欣, 李小泽, 谭维兵, 张立刚, 沈志远, 程攀伦, 宁齐, 梁旭. 金属表面形貌对真空击穿阈值的影响[J]. 太赫兹科学与电子信息学报, 2019, 17(1): 174. 胡祥刚, 宋玮, 向导, 朱晓欣, 李小泽, 谭维兵, 张立刚, 沈志远, 程攀伦, 宁齐, 梁旭. Influence of metal surface morphology on the threshold of vacuum breakdown[J]. Journal of terahertz science and electronic information technology, 2019, 17(1): 174.