Abstract：In a high-powered single pulse device, graphite electrode is better than other ordinary metal electrodes for high energy transfer pulse discharge. This paper mainly investigates the erosion mechanism of graphite electrode with the theory of thermodynamics and experiment results in high energy pulse discharge. Based on thermodynamic principles, the simplified mathematical model of the electrode erosion process is built. Because of the special thermodynamic properties, the duration of temperature rising process on the graphite electrode surface could be ignored, during the microsecond or longer discharges duration. It can be known the relationship between electrode erosion and transfer charge is linear. That can be proved by results of experiments.
[1] 郭良福, 何孟兵, 周圣, 等. 强激光能源系统用气体开关的研究[J]. 高电压技术, 2007, 33(2): 66-70. Guo Liangfu, He Mengbing, Zhou Sheng, et al. Research on gas spark switch for high power laser system[J]. High Voltage Engineering, 2007, 33(2): 66-70. [2] 王清玲, 郭良福, 湛锋, 等. 环形开关电极的自动优化设计方法[J]. 强激光与粒子束, 2006, 18(2): 333-337. Wang Qingling, Guo Liangfu, Shen Feng, et al. Auto-optimization design of ring-shaped switch electrode[J]. High Power Laser and Particle Beams, 2006, 18(2): 333-337. [3] Arnold P A, Hulsey S D, Ullery G T, et al. An update on the status of the NIF power-conditioning system[J]. IEEE Transactions on Plasma Science, 2008, 36(2): 383-388. [4] 李黎, 刘刚, 林福昌, 等. 石墨型高能气体开关的电极使用寿命分析[J]. 中国电机工程学报, 2011, 31(6): 109-115. Li Li, Liu Gang, Lin Fuchang, et al. Analysis on electrode lifetime of high power graphite spark gap switch[J]. Proceedings of the CSEE, 2011, 31(6): 109-115. [5] 何孟兵, 贺臣, 李劲. 气体火花开关电极的烧蚀研究[J]. 高电压技术, 2004, 30(10): 54-55. He Mengbing, He Chen, Li Jin. Research on erosion of gas spark switch electrodes[J]. High Voltage Engineering, 2004, 30(10): 54-55. [6] 何孟兵, 李劲, 姚宗干. 旋转电弧间隙开关的电极烧蚀[J]. 高电压技术, 2002, 28(12): 30-34. He Mengbing, Li Jin, Yao Zonggan. Electrode erosion of rotary arc gap-switches[J]. High Voltage Engineering, 2002, 28(12): 30-34. [7] 姚学玲, 曾正中, 陈景亮. 脉冲电弧对钨铜电极表面侵蚀形态的研究[J]. 高电压技术, 2006, 32(7): 21-24. Yao Xueling, Zeng Zhengzhong, Chen Jingliang. Investigation of WCu electrode erosion morphology under impulse arcs[J]. High Voltage Engineering, 2006, 32(7): 21-24. [8] 庄全超, 魏国祯, 董全峰, 等. 温度对石墨电极性能的影响[J]. 物理化学学报, 2009(3): 406-410. Zhuang Quanchao, Wei Guozhen, Dong Quanfeng, et al. Influence of temperature on the performance of a graphite electrode[J]. Acta Physico-Chimica Sinica, 2009(3): 406-410. [9] Donaldson, A L, Kristiansen, M., The erosion performance of graphite electrodes in high current, high coulomb, spark gaps[C]. Proceedings of the 8th Pulsed Power Conference, 1991. [10] Carslaw H S, Jaeger J C．Conduction of heat in solids[M]. 2nd ed. New York: Oxford University Press, 1959. [11] 白峰, 邱毓昌, 姜惟. 气体火花开关电极材料的冲击电流侵蚀特性[J]. 电工技术学报, 2001, 16(4): 76-79. Bai Feng, Qiu Yuchang, Jiang Wei. Erosion characteristics of the electrodes used for gas spark gap[J]. Transactions of China Electrotechnical Society, 2001, 16(4): 76-79. [12] 何孟兵, 周圣, 李志鹏. 放电电弧电磁力计算与气体开关电极机械性能的选择[J]. 电工材料, 2007(1): 24-26. He Mengbing, Zhou Sheng, Li Zhipeng. Caculation of arc magnetic pressure on electrode surface and choice of electrode mechanical property[J]. Electrical Engineering Materials, 2007(1): 24-26. [13] Nemchinsky V. Cathode erosion rate in high-pressure arcs: influence of swirling gas flow[J]. IEEE Transactions on Plasma Science, 2002, 30(6): 2113-2116. [14] 林福昌, 蔡礼, 李黎, 等. 石墨型气体开关电接触面的温升分析[J]. 中国电机工程学报, 2010, 30(33): 96-102. Lin Fuchang, Cai Li, Li Li, et al. Temperature rise analysis on electrical contact interface of graphite spark gap switch[J]. Proceedings of the CSEE, 2010, 30(33): 96-102. [15] Zhang D, Hill M, McBride J W. Evaluation of the volumetric erosion of spherical electrical contacts using the defect removal method[J]. IEEE Transactions on Components and Packaging Technologies, 2006, 29(4): 711-717. [16] Marakhtanov M K, Marakhtanov A M. Thermionic valve effect and cathode crater rhythm in a low-voltage cold-cathode vacuum arc[J]. Technical Physics Letters, 1998, 24(7): 504(570-572). [17] Daalder J E. Diameter and current density of singe and multiple cathode discharges in vacuum[J]. IEEE Transactions on Power Apparatus Systems, 1974, 93: 1747-1757. [18] Juttner B. Cathode spots of electric arcs[J]. Journal of Phys D: Applied Physics, 2001 (34): 103-123. [19] 张程煜, 乔生儒, 杨志懋, 等. 纯石墨和铜-石墨的阴极斑点与截流值研究[J]. 稀有金属材料与工程, 2009, 38(3): 488-491. Zhang Chengyi, Qiao Shengru, Yang Zhimao, et al. Cathode spot movements and chopping current of pure graphite and copper-graphite in vacuum[J]. Rare Metal Materials and Engineering, 2009, 38(3): 488-491.
2013, Vol. 28 
