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A new kind of pressed Y2O3 doped Ba-W dispenser cathodes are prepared by a sol-gel method combined with high temperature sintering in dry hydrogen atmosphere. The results show that the growth of the grains is hampered by the pinning effect of Y2O3 distributing uniformly on the surfaces of tungsten particles, resulting in the formation of small grain size. It is found that Y2O3 improves the secondary electron emission property, i.e., the secondary emission yield increases with the increase of Y2O3 content in the samples. The maximum secondary emission yield δmax of the cathode with 15% amount of Y2O3 can reach 2.92. Furthermore, the cathode shows a certain thermionic emission performance. The zero field emission current density J0 of 4.18A/cm has reached at 1050oCb for this kind of cathode after being activated at 1200oCb, which are much higher than that of rare earth oxide doped molybdenum (REO-Mo) cathode reported in the previous work. © 2012 IEEE.
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年份: 2012
页码: 181-182
语种: 英文