Damage structure in Al 2O 3 single crystal irradiated with He-ions
Abstract
The microstructures of single crystal alumina irradiated with He-ions at 1023 to 1223 K to a dose of 1 × 10 20 He/m 2 were examined in an electron microscope. In as-irradiated samples, high densities of defect clusters with 6-7 nm in an average size were formed and these were almost independent of the irradiation temperatures. The clusters were revealed to he dislocation loops of interstitial type. In the sample annealed for 1 h at 1223 K after the He-irradiation at 1023 K, five distinguishable features appeared: high density of small cavities with 7 nm in an average size, highly coalesced cavity channels, small sized spherical precipitates of aluminium, large size aluminium islands, and dislocation loops with an average size of 70 nm. These features were revealed to be strongly dependent on the helium irradiation damage and also on the distances of damaged layers from foil surface during annealing.
- Publication:
-
Journal of Nuclear Materials
- Pub Date:
- July 1988
- DOI:
- 10.1016/0022-3115(88)90273-5
- Bibcode:
- 1988JNuM..155..366K