| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a boron carbide-based ceramic where a fracture toughness value being a problem when used as a structural material is improved without significantly losing high specific rigidity possessed essentially by a boron carbide ceramic, where comparatively high strength is maintained and where reliability is satisfied when used for usage moving at a high speed. <P>SOLUTION: There are a boron carbide-silicon carbide composite ceramic having a bending strength at room temperature of 200 MPa or more, a fracture toughness value of 2.5 MPa*m<SP>0.5</SP>or more, a specific rigidity value of 150-180 GPa*cm<SP>3</SP>/g, a composition where at least the content of boron carbide is more than 50 mass%, the content of silicon carbide is less than 50 mass%, the total content of free carbon and other components is 3 mass% or less and the content of aluminum which is one of other components is 1 mass% or less and an average particle diameter of particles in the ceramic of 20 μm or less, and a method for producing the boron carbide-silicon carbide composite ceramic. <P>COPYRIGHT: (C)2011,JPO&INPIT |
