| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1599972 | Intermetallics | 2014 | 6 Pages |
•Helium cavities are formed in both the α2 and γ phases after He-ion irradiation.•The growth of the cavities in the α2 phase is larger than that in the γ phase.•Crystal structure gives rise to differences in radiation behaviour.
A Ti–45Al–2Nb–2Mn + 0.8 vol.% TiB2 (at.%) alloy with fully lamellar microstructure consisting of hexagonal-close-packed (hcp) α2 and face-centred-tetragonal (fct) γ phases was irradiated by implanting helium ions to different fluences. Microstructural examination showed that helium cavities are formed in both the α2 and γ phases after He-ion irradiation. However, the helium cavities and their size change with fluence are much larger in the α2 phase than those in the γ phase, indicating that the γ phase exhibits better tolerance to the He-ion irradiation than the α2 phase. Since α2 and γ phases have different crystal structures, they possess differences in helium solubility and interstitial migration. These differences are responsible for the variation in radiation damage behaviour between the two phases.
