脉冲电场下两种电极材料表面电子发射阈值特性的实验研究∗

摘要

The principle of measuring electron emission threshold of surface area metal electrode is presented. The measurement system of electron emission thresholds of two electrodes is developed. The electron emission characteristics of materials with different roughness degrees or Cr2O3 coating-deposit 40 µm are measured in“Chenguang”accelerator. The results show that polishing can suppress electron emission. The higher the roughness degree of material, the lower the electron emission threshold is. Material coated with Cr2O3 has higher electron emission threshold than polished material.%研究了金属表面电子发射阈值的测量原理。以待测材料为阴极，以法拉第筒作为阳极收集电子。在“晨光号”加速器上，测量了不同粗糙度的304L不锈钢和铝表面电子发射阈值及经表面涂覆工艺处理后这两种电极材料表面电子发射阈值。研究发现：电极表面磨光可以抑制电子发射，随着粗糙度的增加，电子发射阈值降低；金属表面涂覆对抑制电子发射效果更为显著，电子发射阈值增加了一倍。