PURPOSE: To obtain the subject complex sintered material by adding a proper amount of a carbon component to silicon nitride and forming silicon carbide during a sintering process, suitable for a high-temperature structural material, having excellent strength at room temperature and high temperature.
CONSTITUTION: (A) 100mol silicon nitride component comprising 92-99.5mol % silicon oxide-containing silicon nitride (e.g. silicon nitride powder having 0.6μm average particle diameter, 98% α-Si3N4 content and 1.3wt.% oxygen content) and 0.5-8mol% oxide (e.g. Er2O3 having 0.5μm average particle diameter) of an element of group 3a of the periodic table as a sintering auxiliary is blended with (B) 1-100mol% carbon (e.g. carbon powder having 0.1μm average particle diameter). The blend is mixed with as a binder and ground in methanol. The prepared slurry is dried, granulated and press molded under about 1 ton/cm2. The molded article is burnt in a nonoxidizing atmosphere (e.g. nitrogen) at 1,900°C (e.g. 1,600-1,850°C) for about 3 hours. The molded article is subjected to hot press burning or HIP burning in a nonoxidizing atmosphere.
TERASONO MASAKI
UCHIMURA HIDEKI
TAJIMA KENICHI
