高寸法精度・高強度TiB₂/SiCコンポジットの鋳込み成形による作製

抄録

The strength and the size accuracy of TiB₂/SiC composite sintered bodies, which were shaped by the slip cast molding using gypsum molds and hot isostatic pressing (HIP), were investigated. Near net shaped bodies with no cracks were obtained after optimizing the dispersibility of the slurry by adjusting the amount of a dispersant and the pH value. The increase in the solid concentration of the slurry improved the dispersibility of TiB₂ particles that acted as fracture origins in the HIPed body. The four-point flexural strength of the sintered body by HIP was 710MPa, which was same level of that made by hot-pressing. Combustors were fabricated by using this slurry. The standard deviation of each parts, 110mm in diameter was 0.1mm. The coefficient of variation in the size among eleven parts was 0.9%. The flexural strength of the specimen cut from the combustor was also equivalent to that of the hot-pressed body.