负氢离子源负氢离子表面转化材料发展现状分析

负氢离子源已经成为核聚变装置中性束加热系统的首选离子源,中国的负氢离子源研究尚处于起步阶段。在本论文中,介绍负氢离子源的结构和工作过程,比较分析负氢离子的产生模式,着重对当前应用较多、具有应用前景的表面产生模式中负氢离子转化材料进行了介绍。掺铯的金属材料以其优异的特性成为当前负氢离子源的主要材料;La B6热阴极具有较好的负氢离子转化性能,但其复杂的结构和较短的寿命影响了其总体性能;高有序石墨仅仅在结构上具有一定的优势;结合热电子发射、场致电子发射和其他电子发射模式的金刚石膜材料具有较优异的性能预期和较好的前景。因此在未来的负氢离子源中,铯化金属材料和金刚石薄膜材料可能会成为用于表面转化的主要材料。

Latest Development of Surface Conservation Materials in Sources of Negative Hydrogen Ion

The latest advance of negative hydrogen ions (H^-) generation, for Negative Beam Injection (NBI) of fusion reactor, was tentatively reviewed. The discussions with specific examples focused on:i) the source structures and H^--ion generation modes, including the charge exchange generation, surface plasma generation (SPG) and volume generation (VG), and their strengths and weaknesses; ii) the advanced H^--ion surface conversion materials for SPG and VG, including but not limited to the Cs-coating, B-doped poly-diamond films, highly oriented pyrolytic graphite, LaB₆, and surface caesiated Mo-, W-, Ni-, Cu-substrates; and iii) the existing problems and possible solutions, for example, the complicated structure and short service life of LaB₆ hot cathode. Moreover, the extensively research subjects and development trends of the promising H^--ion surface conversion materials, particularly caesiated metals and mono-diamond coatings, were briefly discussed in a thought provoking way.