碳化硅纳米线阴极强流电子束源及其重频运行特性研究

项目名称： 碳化硅纳米线阴极强流电子束源及其重频运行特性研究

项目编号： No.11305263

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 荀涛

作者单位： 中国人民解放军国防科学技术大学

项目金额： 27万元

中文摘要： 强流电子束源阴极是高功率微波系统的核心部件之一，为满足高功率微波源重复频率、长寿命运行的需求，强流阴极需要吸纳新型材料。SiC纳米线是一类新型纳米材料，其外观类似于传统天鹅绒材料，同时具备高熔点、良好的热稳定性及化学稳定性、高的力学强度及电击穿强度，这些特点对于提高阴极在重复频率运行时的使用寿命不无益处。 本项目提出采用SiC纳米线来制备强流电子束源阴极的思路，拟在已成功制备SiC纳米线的基础上，进一步组装为强流发射阴极，并应用于高功率二极管。通过研究SiC纳米线阴极的强流发射特性，阐明其产生阴极等离子体的物理机制，揭示纳米效应对束流发射品质的影响；通过研究高重复频率条件下的脉冲特性，探索影响SiC纳米线强流电子束源运行寿命的因素。本项目的实施对于拓展阴极基础研究和提高强流电子束源的技术性能都具有重要意义。

中文关键词： 强流电子束源；碳化硅纳米线；阴极等离子体；重频运行；脉冲功率

英文摘要： Defense and industrial applications have promoted the development of high-power microwave (HPM) and pulsed power technologies. The remaining challenges of repetitive and long lifetime operation, confronting high-power microwave technology, stimulate intense interest in seeking the new high-current electron beam sources. Due to the speical structrues and remarkable physicochemical properties, one-dimensional nanostructures draw more attention for the potential applcations as the high-current emitters. SiC nanowires combine the advantages of traditional cold cathodes and nanostructures, and exhibit excellent properties with nanoscale tips, large aspect ratio, thermal and chemical stability, which are expected to have benefits for the repetitive and long lifetime operations of the HPM systems. In this research project, based on the ultra-long SiC nanowires, the emission process of the SiC nanowires cathodes will be firstly investigated, theoretically and experimentally. The high-current emission mechanisim of SiC nanowires, the characteristics of the cathode plasma, the beam flow, the beam uniformity and density will be presented and discussed. The relationship between nano-effects and beam quality will be addressed. Further more, the feasibility of repetition rate pulse operation of the SiC nanowire cathode will b

英文关键词： High-current electron beam source；SiC nanowires；cathode plasma；repetitive pulse operation；pulsed power