掺杂氧化铈钡钨阴极的结构和发射性能的研究  

Study on Microstructure and Emission Properties of Ba-W Cathodes Doped with CeO_2

作　　者：卢平[1] 沈春英[1] 丘泰[1] 

机构地区：[1]南京工业大学材料科学与工程学院,江苏南京210009

出　　处：《稀有金属》2008年第1期50-53,共4页Chinese Journal of Rare Metals

摘　　要：采用CeO2与钨粉机械混合,制备了满足大功率微波器件要求的高性能掺杂CeO2钡钨阴极,利用扫描电镜、压汞仪等测试手段分析了阴极的微观结构。用水冷阳极二极管检测了阴极的发射性能。研究表明,掺杂CeO2钡钨阴极孔径分布较窄,为0.4~3.6μm,平均孔径为2μm。在阴极正常工作温度1050℃下,掺杂CeO2钡钨阴极的直流发射电流密度和脉冲发射电流密度分别为6.33,17.48 A.cm-2,明显优于传统钡钨阴极,满足大功率微波器件要求。A new barium-tungsten cathode was prepared by mechanical mixing CeO2 with tungsten matrix.Its microstructure was studied by means of scanning electronic microscope（SEM） and mercury intrusion poremeasurement（MIP）.The emission characteristics were investigated with water-cooled anode diode.The result showed that barium-tungsten cathode doped with CeO2 had symmetrical distribution of pore diameter,0.4～3.6 μm,average pore size was 2 μm.At the normal working temperature（1050 ℃） for cathode,barium-tungsten cathode doped with CeO2 exhibited excellent characteristics of the direct and pulse emission current density,comparing with the conventional barium-tungsten cathode,and its emission current density of direct and pulse were 6.33 and 17.48 A·cm-2,respectively.This emission current density could satisfy the requirements of high-power microwave devices.

关 键 词：稀土 CEO2 钡钨阴极 发射电流密度 

分 类 号：O462[理学—电子物理学]