Liquid phase sintered silicon carbide shaped bodies having improved fracture toughness as well as high electrical resistance and method of making them

摘要

At least three hard phase globular grains of mean size up to 4 mu m surround a triple-point. Each has an SiC core and an Si-C-Al-O-N mixed crystal casing with Al/N atomic ratio of 0.1-2.0. The partially-crystalline binder phase comprises rare earth metal-Al-Si-O. The amorphous phase comprises a globular grain with surrounding boundary film and the crystalline phase is a precipitate of rare earth metal-aluminate. An Independent claim is included for a detailed procedure producing the molding, including e.g. heating, sintering, compaction, preheating, driving off binder, and firing. Details of temperatures, atmospheres, binders and formulation are quantified. Please also see uses.