About this Abstract |
| Meeting |
MS&T25: Materials Science & Technology
|
| Symposium
|
Advances in Refractory High Entropy Alloys and Ceramics
|
| Presentation Title |
Multi-Modal Characterization of the B2 Phase in the Ta-Re Binary System |
| Author(s) |
Bryan Crossman, Junxin Wang, Loic Perrière, Si Athena Chen, Jean-Philippe Couzinié, Maryam Ghazisaeidi, Michael Mills |
| On-Site Speaker (Planned) |
Bryan Crossman |
| Abstract Scope |
Energy and transportation industries require materials that maintain their mechanical properties at high temperatures. Refractory high entropy alloys (RHEAs) with a BCC + B2 microstructure are a potential solution but require a stable B2 phase with a high solvus temperature. We recently predicted the high temperature stability of a TaRe B2 structure using density functional theory. Here, we present experimental evidence of this phase, despite Ta-Re phase diagrams predicting a single-phase BCC microstructure. Scanning electron microscopy characterization of a Ta65Re35 alloy revealed a high Z nanoscale secondary phase at 1550 ℃ and 1100 ℃ . Scanning transmission electron microscopy revealed that this phase is cubic and equiatomic TaRe. B2 superlattice reflections were absent in diffraction patterns due to the similarity in atomic numbers of Ta (73) and Re (75). Neutron diffraction confirmed that the second phase was indeed B2. This allows for the development of new families of BCC+B2 RHEAs. |