| 摘要 |
PURPOSE:To provide a high reliability silicon nitride-based sintered compact excellent in strength and toughness and having slight unevenness in strength. CONSTITUTION:An oxide or nitride sintering aid is added to powdery starting material contg. >=80wt.% beta-silicon nitride by 0.2-12wt.% and they are compacted, fired at 1,600-2,100 deg.C under <=500 atm pressure of gaseous nitrogen and subjected to heat treatment for grain growth at 1,800-2,100 deg.C under >=2atm pressure of gaseous nitrogen to obtain the objective silicon nitride-based sintered compact having <=5% porocity, >=500MPa three-point bending strength, >=40 Weibull modulus and >=7MPa/m fracture toughness. |
