Abstract
Eutectic Al2O3 Y3Al5O12 (YAG) single crystals were fabricated by unidirectional solidification. High-temperature deformation behaviour was examined by uniaxial compression testing in argon flow at temperatures between 1773K and 1973K under an initial strain rate in a range of 2.8 × 10-6 approx. 1 × 10-4 s-1. High-temperature yield stress in Al2O3-YAG single crystal is much higher than that in sintered Al2O3-YAG composite with the same composition. The stress exponent n and the activation energy Q in the single crystal are estimated to be about 6 and about 730 kJ/mol, respectively. The activation energy is nearly the same with that in Al2O3 or YAG single crystal reported previously. In the deformed samples, tangled dislocations are observed in both Al2O3 and YAG single crystals. High-temperature deformation is likely to be controlled by dislocation motion.
| Original language | English |
|---|---|
| Pages (from-to) | 855-862 |
| Number of pages | 8 |
| Journal | Key Engineering Materials |
| Volume | 171-174 |
| Publication status | Published - 2000 Jan 1 |
| Event | Proceedings of the 1999 8th International Conference on Creep and Fracture of Engineering Materials and Structures - Tsukuba, Jpn Duration: 1999 Nov 1 → 1999 Nov 5 |
ASJC Scopus subject areas
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering