| About this Abstract |
| Meeting |
2022 TMS Annual Meeting & Exhibition
|
| Symposium
|
Fatigue in Materials: Fundamentals, Multiscale Characterizations and Computational Modeling
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| Presentation Title |
Spatial and Temporal Slip Heterogeneity in Ti–7Al as a Function of Oxygen Content and Crystallographic Ordering |
| Author(s) |
Felicity F. Worsnop, Rachel Lim, Darren Pagan, Joel Bernier, Yilun Xu, Thomas McAuliffe, David Rugg, Fionn Dunne, David Dye |
| On-Site Speaker (Planned) |
Felicity F. Worsnop |
| Abstract Scope |
Time-dependent, spatially heterogeneous slip is central to the performance of titanium alloys in aero engine applications, exemplified by the cold dwell fatigue phenomenon. Slip localisation in the hcp α phase is influenced by interstitial oxygen content and by crystallographic ordering of aluminium to form Ti3Al α2. The effects of these solutes on slip avalanching (i.e. time intermittency) are not well established. Model alloys Ti–7Al–0.05O and Ti–7Al–0.25O (wt.%) were produced in disordered and ordered states to isolate these factors. In situ high-energy X-ray diffraction microscopy was performed during creep loading, revealing the time-dependent behaviour on the slip systems of hundreds of grains in each polycrystalline specimen. Dislocation configurations after deformation were characterised in TEM. Our experiments demonstrate that, despite their similar effects in promoting spatial localisation of slip, oxygen and α2 have notably dissimilar effects on the time intermittency of slip in α titanium. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Titanium, Mechanical Properties, Characterization |