High current density Sc_2O_3-W matrix dispenser cathode  

作　　者：WANG JinShu ZHANG XiZhu LIU Wei WANG YiMan ZHOU MeiLing ZUO TieYong 

机构地区：[1]School of Materials Science and Engineering,Beijing University of Technology,Beijing 100124,China

出　　处：《Science China(Information Sciences)》2012年第1期98-105,共8页中国科学（信息科学）（英文版）

基　　金：supported by National Natural Science Foundation of China(Grant No.51071005);Doctoral Fund of Ministry of Education of China(Grant No.20101103110018);Beijing Natural Science Foundation(Grant No.2102007);Program for Excellent Talents in Beijing(Grant No.PHR201006101)

摘　　要：Sc2O3-W matrix dispenser cathodes have been prepared by powder metallurgy method and tested in Pierce electron guns. The emission current density can reach 72 A/cm2 at 900℃ and over 100 A/cm2 can be achieved at a temperature higher than 950℃. The emission improves and then keeps stable with time throughout the life testing period of 330 h at a continuous loading of 88 A/cm2 pulsed current density with a pulse width of 10 μs and duty cycle of 0.2%. The cathode surface is covered by a semiconductor multilayer composed of Ba, Sc and O. The emission behavior of the cathode can be explained by a semiconductor model.Sc2O3-W matrix dispenser cathodes have been prepared by powder metallurgy method and tested in Pierce electron guns. The emission current density can reach 72 A/cm2 at 900℃ and over 100 A/cm2 can be achieved at a temperature higher than 950℃. The emission improves and then keeps stable with time throughout the life testing period of 330 h at a continuous loading of 88 A/cm2 pulsed current density with a pulse width of 10 μs and duty cycle of 0.2%. The cathode surface is covered by a semiconductor multilayer composed of Ba, Sc and O. The emission behavior of the cathode can be explained by a semiconductor model.

关 键 词：emission property Scandia doped tungsten CATHODE 

分 类 号：TN873.93[电子电信—信息与通信工程] TQ114.262[化学工程—无机化工]