| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Metastable Phases and Phase Equilibria: Towards Designing the Next Generation of Alloys
|
| Presentation Title |
Harnessing the Stability of 𝜃ʹ-Al2Cu at Unprecedented High Temperatures |
| Author(s) |
Dongwon Shin, Amit Shyam, Larry F. Allard, Matthew F. Chisholm, Jon Poplawsky, J. Allen Haynes |
| On-Site Speaker (Planned) |
Dongwon Shin |
| Abstract Scope |
Oak Ridge National Laboratory recently developed a family of cast Al-Cu alloys that can withstand up to 350°C (>200 hours) without appreciably losing mechanical strength. Extensive characterization has revealed that engineering the Al/𝜃′-Al2Cu interface via microalloying is the key to stabilizing this metastable strengthening phase at unprecedented high-temperatures. Inspired by this stimulating observation, we have performed massively parallelized first-principles density functional theory calculations (DFT) with modern supercomputing to further investigate the underlying mechanism. We present DFT databases of solute segregation energy at the interface between the aluminum matrix and 𝜃′-Al2Cu, and partitioning of solutes within 𝜃′. We also report Al/𝜃′ interfacial energies at under-investigated orientation obtained from DFT calculations of the experimentally observed structures. The research was sponsored by the LDRD Program of Oak Ridge National Laboratory and the Department of Energy, Vehicle Technologies Office, Propulsion Materials Program. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |