Process for producing thermal shock-resistant silicon nitride sintered material

摘要

There is provided a thermal shock-resistant silicon nitride sintered material including silicon nitride and rare earth element compounds, which material contains at least 10 pore groups per mm2, each pore group consisting of pores of 10 or less in diameter and which material has a thermal shock resistance DELTA Tc ( DEG C.) of 1,000 DEG C. or more. The thermal shock-resistant silicon nitride sintered material can be produced by mixing and shaping starting materials consisting of silicon nitride powders of rare earth element oxides and carbide powder, and then firing the shaped material in a nitrogen atmosphere to decompose the carbide powders.