摘要
探索提高金属表面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,采用有限元法计算阴极杆表面电场随二极管电压的变化规律,设计了实验系统,并开展了实验研究。实验对比了在脉宽约30 ns、阴极杆与阳极筒间隙12 mm时,钛合金TC4阴极杆在不同种类高分子膜(膜厚30~60μm)下真空击穿阈值的变化情况。在表面粗糙度Rz(轮廓最大高度)为0.8μm的TC4阴极杆表面分别镀环氧树脂膜和丙烯酸膜,实验结果表明,镀丙烯酸膜阴极杆的击穿阈值约505 kV/cm,相对于不镀膜阴极杆,击穿场强提高了约20.6%;在表面粗糙度Rz为0.2μm的TC4阴极杆表面分别镀聚酰亚胺膜和聚醚醚酮膜,实验结果表明,镀聚酰亚胺膜阴极杆的击穿阈值为584 kV/cm,相对于不镀膜阴极杆,击穿场强提高了约28.1%。因此,在金属表面镀丙烯酸膜、聚酰亚胺膜可以有效提高金属表面的真空击穿阈值。
It is of great significance for the development and application of pulse power technology to explore ways to improve the vacuum breakdown threshold of metal surface.Based on the theoretical analysis of electron on metal surface,the variation of surface electric field of cathode rod with diode voltage is calculated by finite element method.Experimental system is designed and experimental research is carried out.The experiment compares the vacuum breakdown threshold of TC4 of titanium alloy under different kinds of dielectric films(film thickness 30−60μm),when the pulse width is about 30 ns and the gap between cathode rod and anode tube is 12 mm.The TC4 cathode rods with a surface roughness Rz(maximum outline height)of 0.8μm are plated with epoxy resin and acrylic acid film respectively.The experimental results show that the breakdown threshold of the acrylic acid coated cathode rod is about 505 kV/cm.Compared with the uncoated cathode rod,the breakdown field strength is increased by about 20.6%;The TC4 cathode rods with surface roughness Rz of 0.2μm are plated with polyimide film and polyether-etherketol film respectively.The experimental results show that the breakdown threshold of the polyimide film coated rod is about 584 kV/cm.The breakdown field strength is enhanced by approximately 28.1%,relative to the non-coated cathode rod.Therefore,coating acrylic acid film and polyimide film on the surface of metal cathode rod can effectively improve the vacuum breakdown threshold of metal rod.
作者
胡祥刚
苏建仓
张瑜
朱晓欣
李小泽
谭维兵
张立刚
Hu Xianggang;Su Jiancang;Zhang Yu;Zhu Xiaoxin;Li Xiaoze;Tan Weibing;Zhang Ligang(Science and Technology on High Power Microwave Laboratory,Northwest Institute of Nuclear Technology,P.O.Box 69-13,Xi’an 710024,China)
出处
《强激光与粒子束》
EI
CAS
CSCD
北大核心
2020年第7期115-119,共5页
High Power Laser and Particle Beams
基金
高功率微波技术重点实验室课题。
关键词
场致爆炸发射
纳秒脉冲
高分子膜
真空击穿阈值
field-induced explosive electron emission
nanosecond pulse
polymer film
vacuum breakdown threshold