Relationship between microstructure, toughening mechanisms, and fracture toughness of reinforced silicon nitride ceramics
- Max-Planck-Inst. fuer Metallforschung, Stuttgart (Germany)
- Slovak Academy of Sciences, Kosice (Slovakia). Inst. of Materials Research
Different microstructures in Si{sub 3}N{sub 4} ceramics containing Y{sub 2}O{sub 3} and Al{sub 2}O{sub 3} as sintering additives were prepared by two-step sintering. Pull-out and elastic bridging were most frequently observed as the toughening mechanisms in samples with fine-grained microstructures having needlelike {beta}-Si{sub 3}N{sub 4} grains with diameters of < 1 {micro}m. Crack deflection was the main toughening mechanism observed in samples with coarse-grained microstructures having grains with diameters of > 1 {micro}m. The values of fracture toughness were varied from 6.1 to 8.2 MPa {center_dot} m{sup 1/2} with respect to the microstructural characteristics, characterized by the volume fraction of needlelike grains and their diameter.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 131526
- Journal Information:
- Journal of the American Ceramic Society, Journal Name: Journal of the American Ceramic Society Journal Issue: 10 Vol. 78; ISSN 0002-7820; ISSN JACTAW
- Country of Publication:
- United States
- Language:
- English
Similar Records
Thermal conductivity of in-situ reinforced silicon nitride
Barium aluminosilicate reinforced in situ with silicon nitride