| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for producing microparticles of LaB<SB POS="POST">6</SB>which are high in purity and small in particle size, the microparticles concerned being suitable as a powdery raw material for producing a sintered compact of LaB<SB POS="POST">6</SB>. <P>SOLUTION: The method for producing the microparticles of lanthanum hexaboride includes; (a) a process in which the microparticles of a lanthanum compound, which have an average particle size of at least 20 nm and at most 220 nm, and the microparticles of a boron compound, which have an average particle size of at least 20 nm and at most 10 μm, are mixed together in a solvent and a resin so that the atom ratio B/La may be at most 4; (b) a process in which the liquid mixture is dried; (c) a process in which the dried material is carbonized in vacuum or in an inert gas atmosphere, and then the carbonized material is subjected to heating processing at the lowest 1,150°C and at the highest 1,600°C in vacuum, in a reductive atmosphere or in an inert gas atmosphere; and (d) a process in which the heat-processed material is subjected to heating and oxidizing processing at the lowest 500°C and at the highest 800°C in the air atmosphere, and then the material thus obtained is subjected to acid processing in an inorganic acid. In the process (a), the mass of the resin is at least 0.5 mass% and at most 10 mass% to the total mass of the microparticles of the lanthanum compound and boron compound. <P>COPYRIGHT: (C)2013,JPO&INPIT |
