About this Abstract |
Meeting |
2nd World Congress on High Entropy Alloys (HEA 2021)
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Symposium
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2nd World Congress on High Entropy Alloys (HEA 2021)
|
Presentation Title |
Ab Initio Study of the Phase Stability and Transition-induced Plasticity of Body-centered Cubic Refractory High-entropy Alloys |
Author(s) |
Yuji Ikeda, Prashanth Srinivasan, Konstantin Hubaev, Fritz Körmann, Blazej Grabowski |
On-Site Speaker (Planned) |
Prashanth Srinivasan |
Abstract Scope |
Recent experiments revealed for several body-centered cubic (bcc) refractory high-entropy alloys (HEAs) the ability to improve their ductility by enabling transition-induced plasticity (TRIP), transforming bcc to hexagonal close-packed (hcp) structure. However, the instability of the bcc phase is also often related to the ω phase, whose precipitates are also found in bcc HEAs and can cause embrittlement. To design alloys with improved mechanical properties, the knowledge of the detailed phase stability of such HEAs is essential. We present a thermodynamic and dynamic stability analysis of bcc refractory HEAs from ab initio. We demonstrate that it is essential to first analyze whether alloys relax to a bcc or ω phase. Based on the proposed structure descriptor, ab initio predicted bcc–hcp phase stability threshold compositions are found close to the experimentally observed TRIP compositions in Ti–Zr–Nb–Hf–Ta-based HEAs, opening an avenue for high-throughput alloy design strategies. |
Proceedings Inclusion? |
Undecided |