| 摘要 |
A lanthanum boride sintered body 10 includes a phase 16 including lanthanum and silicon at grain boundaries 14 between crystal grains 12 of lanthanum boride. In this lanthanum boride sintered body 10, the phase 16 exists in various configurations such as a phase 16a present at a triple point of grain boundary 14, and a phase 16b present along the grain boundary 14. This phase 16 is based on a lanthanum silicide (represented by the composition formula LaSi x (0 < x ‰¤ 2)). The lanthanum boride sintered body 10 is fabricated through a sintering step of sintering a lanthanum boride green compact by press-free sintering in an inert atmosphere or under vacuum in the presence of a silicon-containing material around and/or within the green compact. The lanthanum boride sintered body 10 having this structure exhibits a relative density of not less than 92%, and more preferably not less than 94%. |
