Enhanced in situ toughening of silicon nitride by the addition of {beta}-Si{sub 3}N{sub 4} whiskers
- Case Western Reserve Univ., Cleveland, OH (United States)
- Analex Corporation, Brookpark, OH (United States)
- Cleveland State Univ., OH (United States)
Silicon nitride ceramics were processed with the addition of small quantities of {beta}-Si{sub 3}N{sub 4} whiskers to a commercially available {alpha}-Si{sub 3}N{sub 4} powder. These whiskers grew preferentially during liquid phase sintering into very large, elongated {beta}-grains. Silicon nitride samples of the same compositions, but without the whiskers were also processed. The fracture toughness and R-curve behavior of the whisker seeded samples were compared to those of unseeded samples. The fracture toughness of the seeded samples was higher because grain pullout and crack bridging were enhanced by the very large, elongated {beta}-grains. R-curve behavior was present in both seeded and unseeded silicon nitrides.
- OSTI ID:
- 96557
- Report Number(s):
- CONF-940416--
- Country of Publication:
- United States
- Language:
- English
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