| タイトル | Hydride structures in Ti-aluminides subjected to high temperature and hydrogen pressure charging conditions |
| 著者（英） | Robertson, I. M.; Birnbaum, H. K.; Legzdina, D. |
| 著者所属（英） | Illinois Univ. |
| 発行日 | 1991-06-01 |
| 言語 | eng |
| 内容記述 | The distribution and chemistry of hydrides produced in single and dual phase alloys with a composition near TiAl have been investigated by using a combination of TEM and X-ray diffraction techniques. The alloys were exposed at 650 C to 13.8 MPa of gaseous H2 for 100 h. In the single-phase gamma alloy, large hydrides preferentially nucleated on the grain boundaries and matrix dislocations and a population of small hydrides was distributed throughout the matrix. X-ray and electron diffraction patterns from these hydrides indicated that they have an fcc structure with a lattice parameter of 0.45 nm. EDAX analysis of the hydrides showed that they were enriched in Ti. The hydrides were mostly removed by vacuum annealing at 800 C for 24 h. On dissolution of the hydrides, the chemistry of hydride-free regions of the grain boundary returned to the matrix composition, suggesting that Ti segregation accompanied the hydride formation rather than Ti enrichment causing the formation of the hydride. |
| NASA分類 | METALLIC MATERIALS |
| レポートNO | 91A42168 |
| 権利 | Copyright |
| URI | https://repository.exst.jaxa.jp/dspace/handle/a-is/347485 |
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