Compressive Creep and Oxidation Resistance of an Si 3 N 4 Material Fabricated in the System Si 3 N 4 ‐Si 2 N 2 O‐Y 2 Si 2 O 7

The compressive creep behavior and oxidation resistance of an Si 3 N 4 /Y 2 Si 2 O 7 material (0.85Si 3 N 4 +0.10SiO 2 +0.05Y 2 O 3 ) were determined at 1400°C. Creep re sistance was superior to that of other Si 3 N 4 materials and was significantly in creased by a preoxidation treatment (1600°C /120 h). An apparent parabolic rate constant of 4.2 × 10 −11 kg 2 ·m‐ 4 ·s −1 indicates excellent oxidation resistance.