About this Abstract |
Meeting |
2025 TMS Annual Meeting & Exhibition
|
Symposium
|
Computational Thermodynamics and Kinetics
|
Presentation Title |
The Strength of Refractory High Entropy Alloys and Its Connection to Atomic Size Imperfections |
Author(s) |
Jaime Marian |
On-Site Speaker (Planned) |
Jaime Marian |
Abstract Scope |
Refractory high entropy alloys (RHEA) are promising candidates as high-temperature structural materials due to an outstanding combination of strength, fracture toughness, and creep resistance. Certain RHEA have been seen to retain strengths well above 1000C, considerably surpassing the best industry-standard Ni-based superalloys. However, the fundamental causes behind this display of high-temperature strength are still under active investigation. Here we present a theoretical model based on the presence of atomic-level defects as the controlling elements of the alloy plastic response. The model overcomes the inability of models based on rules of mixtures to predict RHEA behavior, and explains the preponderant role played by edge dislocations observed in some experiments. We focus on one of the most popular quaternary systems, the equiatomic Nb-Mo-Ta-W alloy, for which suitable interatomic potentials exist, and from which we obtain all model parameters. The model predictions are consistent with experimental yield-strength measurements in a wide temperature range. |
Proceedings Inclusion? |
Planned: |
Keywords |
Modeling and Simulation, High-Entropy Alloys, Computational Materials Science & Engineering |