| 摘要 |
PURPOSE:To stabilize strength and fracture toughness and to decrease the fluctuation in the characteristics of a sintered body for calcining a specific raw material compsn. CONSTITUTION:The raw material compsn. mixed with (a) at least one kind of the carbides selected from group IVa to VIa elements of the periodic table (e.g.: TiC), (b) an oxide (precursor) contg. at least one kind of the elements selected from group IVa to VIa elements of the periodic table (e.g.: TiO2), (c) at least one kind of the materials which are selected from group IVa to VIa elements of the periodic table, contain boron, exclusive of boride, and have <=10mum average grain size (e.g.: B4C), and if necessary (d) carbon of <=1mum diameter (e.g.: carbon black) and/or org. material forming carbon by pyrolysis (e.g. phenolic resin), and (e) a sintering assistant (e.g.: MgO) is provided. This compsn. is then molded and is sintered at 1500 to 2200 deg.C in a vacuum or nonoxidation atmosphere to obtain the composite material consisting of 95 to 5vol.% at least one kind of the carbides selected from group IVa to VIa elements of the periodic table and 5 to 95vol.% at least one kind of the borides selected from group IVa to VIa elements of the periodic table. |
