碳纤维阴极发射均匀性的实验研究

 分别用自制浸渍碘化铯（CsI）针式环状碳纤维阴极和环状不锈钢阴极所产生的电子束轰击尼龙目击靶，研究碳纤维阴极发射均匀性。在碳纤维阴极电子束轰击的目击靶上得到了均匀的烧蚀痕迹，而不锈钢阴极电子束轰击的目击靶上烧蚀痕迹不均匀，表明碳纤维阴极发射电子束的均匀性优于不锈钢阴极。分析认为两阴极不同的发射机制及其所特有的材料性质和结构导致其发射电子束均匀性的差异。用光学显微镜和电子显微镜对不锈钢阴极尖端和碳纤维阴极尖端和侧面进行扫描，发现不锈钢阴极仅尖端处被烧蚀，而碳纤维阴极尖端和侧面都有烧蚀痕迹，验证了碳纤维阴极由场发射和表面闪络共同作用的发射机制的假设分析。

Experimental investigation on emission uniformity of carbon fiber cathode

The electron beams produced by the needle-shaped annular carbon fiber-coated cathode soaked with cesium iodide (CsI) salt and annular stainless steel cathode were separately used to bombard the nylon targets.There was a uniform round mark on the target bombarded by the electron beam generated by the carbon fiber cathode,but there was a nonuniform mark on the target bombarded by the annular stainless steel cathode.It was believed that the different mechanism,characteristics and configuration between the carbon fiber cathode and the stainless steel cathode caused the difference of emission uniformity.Scanning with optics microscope,it was found that only the tips of the needle-shaped steel was destroyed.With electron microscope,it was found that both the tips and flanks of the carbon fiber were destroyed.Therefore,it was testified that the emission mechanism of metal cathode was explosive electron emission and the emission mechanism of carbon fiber cathode included both field-explosive electron emission and surface flashover.