About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
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Symposium
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Advances in Multi-Principal Elements Alloys X: Structures and Modeling
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Presentation Title |
First-principles-based High-throughput Prediction of the Phase Stability of Refractory Complex Concentrated Alloys |
Author(s) |
Zhaohan Zhang, Mu Li, John Cavin, Katharine Flores, Rohan Mishra |
On-Site Speaker (Planned) |
Zhaohan Zhang |
Abstract Scope |
The ability to predict the composition- and temperature-dependent stability of refractory complex concentrated alloys (RCCAs) is vital to the design of high-temperature structural alloys. We propose that pairwise mixing enthalpies are a key descriptor for predicting the formation enthalpy of multicomponent solid solutions and apply it to screen over 20,000 compositions. We develop a database that contains the pairwise mixing enthalpies of 17 refractory elements with density-functional-theory (DFT) calculations and use these data to fit thermodynamic models that accurately predict the mixing enthalpies of BCC RCCAs. By combining the enthalpy models with DFT-calculated intermetallic enthalpies from the Materials Project database and using convex hull analyses, we can predict the ground-state phase given alloy composition and temperature. The predictions in NbTiZr-V-(Mo, Ta, Cr) systems agree well with experimental observations. Finally, we use this model to predict phase evolution in NbVZr-Tix (0 < x < 1), which are confirmed using laser processing. |
Proceedings Inclusion? |
Planned: TMS Journal: Metallurgical and Materials Transactions |
Keywords |
High-Entropy Alloys, Computational Materials Science & Engineering, High-Temperature Materials |