| 摘要 |
PURPOSE:To improve uniformity, high-temp. strength, etc., at the time of producing an Si3N4-SiC composite sintered compact by hot-press sintering by placing the powder compact in a sintering die with a cavity left between it and the die side wall and sintering the compact. CONSTITUTION:A sintering assistant (e.g. Y2O3) is added to the amorphous powder composed of silicon, carbon, nitrogen and oxygen and wet-mixed, and the mixture is dried. The powder is compacted, the compact 3 is arranged on a spacer 4 in a sintering die 2 with a cavity left between it and the die side wall. A punching rod 5 is set on the compact 3, the atmospheric gas is replaced by gaseous nitrogen, and the compact is heated and hot-press sintered. Consequently, a large-diameter and uniform silicon nitride-silicon carbide composite sintered compact excellent in strength is obtained. The sintered compact is appropriately used as the high-temp. and high-strength member for the gas turbine, engine, etc. |
