钡钨阴极电子发射物411铝酸盐研究  

Emission Characteristics of 411 Aluminates in Ba-W Cathode

作　　者：唐志兰[1] 沈春英[1] 李志顺[2] 丘泰[1] 

机构地区：[1]南京工业大学材料科学与工程学院,南京210009 [2]南京三乐电子信息产业集团有限公司电子器件研究所,南京211800

出　　处：《真空科学与技术学报》2011年第3期305-308,共4页Chinese Journal of Vacuum Science and Technology

摘　　要：采用高温固相反应法合成钡钨阴极用411铝酸盐,研究了在湿空气中放置前后铝酸盐的稳定性、与钨基的浸渍情况、物相的变化和阴极的发射性能。结果表明:在湿空气中放置的411铝酸盐,增重大于9%,与钨基的浸渍性下降,主晶相由Ba3CaAl2O7转变为Ba7Al2O10,BaCO3和CaCO3,在1050℃时,阴极的发射性能从25.86 A·cm-2下降到16.42 A·cm-2,在空气中放置的铝酸盐制备的阴极发射性能降低了36.5%。The 411 aluminate was prepared by high temperature solid phase reaction of a mixture of BaCO3,CaCO3 and Al2O3 powders with the 4∶1∶1 ratio,for the fabrication of Ba-W cathode.The influence of relative humidity during long time storage on its properties,such as emission characteristics,stability,and impregnation with tungsten sponge,was experimentally studied.The results show that the humidity inversely affects the microstructures,properties and stability of the 411 aluminate.For instance,humidity in air increased its weight by 9%;reduced its impregnation in W-matrix,changed the dominant phase from Ba3CaAl2O7 phase into a mixed phases of Ba3Al2O7,BaCO3,and CaCO3.Worse,the moisture treatment reduced its emission current density of the cathode at 1050℃ from 25.86 A·cm-2 to 16.42 A·cm-2,a reduction by 36.5%

关 键 词：411铝酸盐 钡钨阴极 电子发射物质 发射性能 

分 类 号：TG742[金属学及工艺—刀具与模具]