中文摘要：

用氢直流电弧法制备LaH2纳米粉末，再采用放电等离子烧结（SPS）技术，在压力50MPa，烧结温度1400℃～1600℃条件下制备了LaB6亚微米多晶块体。采用EBSD技术，对LaB6样品表面的晶粒、晶界特征及晶粒取向等进行了测试分析。结果表明，SPS制备的LaB6晶粒尺寸为0．14μm～1．10μm，晶粒大小随烧结温度升高而增大。随烧结温度的升高，小角度晶界（微取向差在10°以内）的含量逐渐增加。取向分析表明，SPS烧结LaB6多晶块体形成了几种择优取向。

英文摘要：

Hydrogen arc plasma method was used for preparing La-LaH2 nanopowders, and then the sub-micron bulk polycrystal LaB6 were fabricated by Spark Plasma Sintering（SPS） method at 50 MPa, 1 400℃-1 600℃ . The feature of crystal grain and grain boundary, grain orientation were investigated by means of electron backscatter diffraction（EBSD）. The experimental results show that the grain sizes of LaB6 bulk prepared by SPS is 0.14 μm- 1.10 μm, and the grains grow up with the rise of sintering temperature. The fraction of small anglegrain boundaries（ 〈 10μ）increase with the rise of sintering temperature. The analysis of orientation indicates there are some preferred orientations in the bulk polycrystal LaB6 fabricated by SPS.