| 摘要 |
PURPOSE: To obtain the subject composite sintered compact with high denseness, improved in high-temperature strength, by incorporating a powder mixture of silicon carbide and silicon nitride with a specific sintering auxiliary and boron plus carbon followed by firing under specified conditions. CONSTITUTION: A powder mixture composed of 50-85wt.% of Si3 N4 powder 0.01-1μm in average particle diameter and 15-50wt.% of silicon carbide powder 0.01-1μm in average particle diameter is incorporated with a sintering auxiliary powder consisting of either Al2 O3 or AlN and/or group 3A or 4A oxide in such an amount that the weight ratio of the Al2 O3 plus AlN to the oxide stands at (2:1) to (1:15), 0.3-5wt.% of noncrystalline boron powder <=1μm in average particle diameter plus carbon such as graphite or carbon black <=5μm in average particle diameter, a dispersion medium, and a binder, obtaining a molded form. The molded form is then baked at >=200 deg.C in a gas under a pressure of <=50kg/cm<2> to obtain the objective composite sintered compact. |
