Abstract: CeHx nano-powders were prepared by hydrogen arc plasma method, and then the mixed powders of nano-CeH_x 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/mm² and 254.2MPa. The electron emitting density of the CeB₆ sintered by SPS is 20.38A/cm² 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.

Key words: spark plasma sintering (SPS), reactive liquid phase sintering, polycrystalline cerium hexaboride, property