| 摘要 |
PROBLEM TO BE SOLVED: To obtain a complex sintered body complexly organized by a process similar to a usual one by specifying an average particle size of silicon nitride particles and bringing silicon oxide nitride particles to columnar particles specified in an average particle size and an aspect ratio in a silicon nitride-based complex sintered body consisting of the β-type silicon nitride particles, the silicon oxide nitride particles and an intergranular phase and having a specific relative density. SOLUTION: This complex sintered body of silicon nitride consists of 60-95wt.% of β-type silicon nitride particles, 3-25wt.% of silicon oxide nitride particles and 2-15wt.% of an intergranular phase and has >=95% relative density. In the sintered body, an average particle size of the silicon nitride particles is <=0.45μm, an average particle size of the silicon oxide nitride particles is 0.5-3.0μm and the silicon oxide nitride particles are columnar particles having >=4 aspect ratio. This silicon nitride-based complex sintered body is obtained by baking 75-97wt.% of fine powdery silicon nitride having >=20m<2> /g specific surface and >=85% β factor with adding a baking assistant containing >=1wt.% of silica and >=0.1wt.% of Y2 O3 or Al2 O3 . |
