| 摘要 |
PROBLEM TO BE SOLVED: To produce silicon nitride composite ceramics excellent in high strength, high toughness and wear resistance and applicable to structural materials. SOLUTION: By volume, 3 to 30% TiC, TiN or SiC and 1 to 5% W or Mo are dispersed into the crystal grains of a silicon nitride matrix having <=10μm crystal grains and/or into the boundaries thereof to form silicon nitride composite ceramics. The powdery mixture obtd. by the above blending compsn. is added with a sintering assistant by 5 to 10wt.%, which is subjected to compacting and is thereafter sintered at >=1,600 deg.C in an inert atmosphere. Since the material structure is homogenized and its strength and toughness are improved by the dispersed grains having nano-size, the strength can be maintained. |
