About this Abstract |
Meeting |
2020 TMS Annual Meeting & Exhibition
|
Symposium
|
Fatigue in Materials: Fundamentals, Multiscale Characterizations and Computational Modeling
|
Presentation Title |
Oxygen, α2, Macrozones and Dwell Fatigue Initiation in α-Ti |
Author(s) |
Felicity F. Worsnop, Paraskevas Kontis, Baptiste Gault, Jan Ilavsky, Joel V. Bernier, David Rugg, David Dye |
On-Site Speaker (Planned) |
Felicity F. Worsnop |
Abstract Scope |
Predictive capability for fatigue in critical rotating parts in aero engines is essential for safe and efficient operation. Fatigue crack initiation is thought to occur by pri<a> slip bands proceeding across similarly oriented hcp α grains in a macrozone to cause high localised stress upon impingement on a grain poorly oriented for slip. Ordered Ti3Al α2 precipitates and interstitial oxygen promote slip heterogeneity by suppressing cross-slip, promoting localisation into slip bands. Comprehensive characterisation of α2 formation and growth across a model alloy series using TEM, APT and SAXS, incorporating different interstitial O contents, was followed by exploration of dislocation behaviours with TEM. Mesomechanical stress evolution has been explored using ff-HEDM to observe spatial and temporal slip heterogeneity during in situ deformation. |
Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |