Preparation and Evaluation of Si-Al-O-N.
Abstract
The purpose of this program was to prepare specimens of Si-Al-O-N compositions of adequate intrinsic (i.e., pore-free, high single phase) constitution and size to permit evaluation of chemical, physical, and mechanical properties. A wide variety of processing techniques, including hot pressing, pseudoisostatic hot pressing, cold pressing and sintering, and combinations of these techniques, using beta silicon nitride, alpha silicon nitride, alpha alumina, active alumina, silicon, aluminum nitride, magnesia, and other materials as precursors were employed. Modulus of rupture and elasticity measurements made on representative samples give low strength values compared with Arrol's data (120,000 psi). An explanation for the low strength data may be found in the type of fracture obtained. The scanning electron microscope reveals a fine grain intergranular failure. Further evidence suggests liquid phase sintering at high temperature, which could produce a glassy grain boundary.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1973
- Accession Number
- ADA021997
Entities
People
- A. Z. Hed
- L. E. Shipley
- W. B. Crandall
Organizations
- IIT Research Institute