| 摘要 |
Multi-batch assembly comprises individual weighed reaction mixes of silicon and cpds. contg. O2, sepd. by inert spacers, and contained in a graphite sleeve lined with refractory metal foil; sleeve is treated for inertness and Mo, Nb, Ta or W foil is 0.02 in. or less thick and impervious to C migration. Assembly is heated below Si m.pt. in nitriding atmos. to form partly sintered bodies contg. Si3N4, 5-17% oxynitride and less than 0.5% unreacted O2-contg. cpds. Si nitrided bodies are heat fused at pref. 1600-1760 deg.C and 2500-3800 psi. |
