中文摘要：

以氢直流电弧法制备CeHx纳米粉末,再采用放电等离子（SPS）反应液相烧结纳米CeHx和微米B的混合粉末,制备了高性能CeB6多晶块体热阴极材料.研究了SPS制备CeB6的烧结反应式及反应液相烧结机制,确定SPS烧结CeB6的最佳工艺为： 压力50MPa,烧结温度1500℃,保温时间5min.实验结果表明,SPS制备得到了高纯单相CeB6多晶块体,纯度达到99.89％,相对密度达到99.61％,维氏硬度达到2051kg/mm^2,抗弯强度达到254.2MPa.样品在1600℃温度下拐点发射电流密度达到20.38A/cm^2,功函数为2.42eV.与传统制备法相比,SPS制备显著降低了CeB6的烧结温度,缩短了烧结时间,提高了力学和发射性能.

英文摘要：

CeHx nano-powders were prepared by hydrogen arc plasma method,and then the mixed powders of nano-CeHx and micron boron were sintered by Spark Plasma Reactive Liquid Phase Sintering （SPS） method to fabricate high-properties polycrystalline bulk CeB6 cathodes.The reaction equation of sintering CeB6 and reactive liquid phase sintering mechanism were studied.The optimum process parameters are listed as follows,pressure of 50MPa,temperature of 1500℃,and holding time of 5min.The experimental results show that the CeB6 sintered body with purity of 99.89% and relative density of 99.61% is single-phase of cerium hexaboride.The hardness and bend strength of the sintered CeB6 reach 2051kg/mm^2 and 254.2MPa.The electron emitting density of the CeB6 sintered by SPS is 20.38A/cm^2 at 1600℃,the work function is 2.42eV.In contrast to traditional preparation method,SPS method obviously reduces the sintering temperature and shortens the sintering time of CeB6,and improves the mechanics and emission properties.