摘要
针对微阴极电弧推力器(μ-CAT)应用开展了真空沿面电弧放电过程和产物特性研究,结合放电参数、辐射光谱和高速图像诊断,研究电脉冲作用下放电等离子体形成和演变过程,分析不同磁场下等离子体通道和羽流时空演化规律;收集喷溅产物进行形貌分析,对比不锈钢和钛电极下放电烧蚀产物的宏、微观特性。结果表明,放电起始于“电极−真空−涂层”的三结合点,随后涂层局部放电形成沟通两电极的沿面放电通道;外施100 mT量级的磁场能够改善放电连续性和羽流形貌(发光截面可达无磁场时的2倍);放电结束后,电极热产物喷射过程可持续50~60μs,且阴、阳极存在差异。从收集到的喷溅产物来看,金属电极材料的沉积以均匀分布的纳米颗粒为主,而电极上方Si片沉积呈现微米级无定形石墨形貌。电极烧蚀典型喷溅产物和熔池特征受到电极材料的影响,不锈钢相对于钛电极的产物粒径及电极烧蚀坑尺径更大。因此,磁场、电极材质对真空沿面放电过程及产物形貌有一定影响,从而对μ-CAT性能产生影响。
This paper studies the characteristics of vacuum surface arc discharge process and products for micro-cathode arc thruster(μ-CAT).The formation and evolution process of discharge plasma under the action of the electric pulse is studied and the spatial-temporal evolution of plasma channel and plume under different magnetic fields is analyzed by combining with discharge parameters,radiation spectrum and high-speed image diagnosis.The macro and micro characteristics of the discharge ablation products with stainless steel and titanium electrodes are obtained by collecting the splash products for morphology analysis.The results indicate that the discharge initiates from the electrode triple junction(TJ),and then partial discharge of the coating forms a surface discharge channel connecting the two electrodes.Applying a magnetic field of 100 mT magnitude can improve the discharge continuity and plume morphology(the luminous cross-section can reach two times that in the absence of magnetic field).After discharge,the electrode thermal product spray can last for 50~60μs,and there are differences between the cathode and anode.From view of the collected splash products,the deposition of metal electrode materials is mainly composed of uniformly distributed nanoparticles,while the Si wafer above the electrode presents the morphology of micron-sized amorphous graphite.The typical characteristics of the splash products and electrode ablation pool are affected by the electrode material.The product particle size and electrode ablation pit size of stainless steel are more affected than those of titanium electrodes.Therefore,the magnetic field and electrode material have a significant impact on the vacuum surface discharge process and product morphology Consequently,these factors directly affect the performance ofμ-CAT.
作者
白洁
吴佳玮
耿金越
王亚楠
王芝
韩若愚
BAI Jie;WU Jiawei;GENG Jinyue;WANG Ya’nan;WANG Zhi;HAN Ruoyu(State Key Laboratory of Mechatronics Engineering and Control,Beijing Institute of Technology,Beijing 100081,China;Global Energy Interconnection Development and Cooperation Organization,Beijing 100031,China;Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China;School of Electrical Engineering,Xi’an Jiaotong University,Xi’an 710049,China)
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2023年第9期3835-3847,共13页
High Voltage Engineering
基金
国家自然科学基金(12275019,52007147,52277134)
中国科协青年人才托举工程(2022QNRC001)
北京控制工程研究所先进空间推进技术实验室和北京市高效能及绿色宇航推进工程技术研究中心开放基金项目(LabASP2020-09)。
关键词
脉冲放电
微阴极电弧推力器
真空电弧
图像诊断
电极烧蚀
pulse discharge
micro-cathode arc thruster
vacuum arc
image diagnosis
electrode ablation
