About this Abstract |
| Meeting |
2027 TMS Annual Meeting & Exhibition
|
| Symposium
|
Radiation Effects in Solid-State Materials: An SMD Symposium Honoring William J Weber
|
| Presentation Title |
Chemically Mediated Defect Energetics Govern Radiation Tolerance in a Bulk WTaCrVHf Refractory High-Entropy Alloy |
| Author(s) |
Shalini Tripathi, Skye Supakul, Eda Aydogan, Matthew Vigil, Bochuan Sun, Jesper Byggmästar, Wei-Ying Chen, Enrique Martinez Saez, Dan Thoma, Matthew Olszta, Saryu Fensin, Osman Atwani |
| On-Site Speaker (Planned) |
Shalini Tripathi |
| Abstract Scope |
Radiation-induced defect coalescence and helium bubble growth limit the performance of tungsten in fusion and advanced fission systems. Here, we investigate defect evolution in a vacuum arc-melted coarse-grained WTaCrVHf refractory high-entropy alloy following dual-beam Kr⁺ + He⁺ irradiation at 900 °C to 5 dpa. Transmission electron microscopy reveals uniformly distributed defect loops and helium cavities with average diameters below ~3 nm, without evidence of coarsening. Volumetric swelling remains negligible compared with pure tungsten irradiated under similar conditions. X-ray diffraction confirms a chemically disordered BCC solid solution without irradiation-induced phase formation. Molecular dynamics simulations show that chemical complexity generates a broad distribution of vacancy formation energies and migration barriers, suppressing long-range defect transport while enhancing local recombination. These findings demonstrate that radiation tolerance in bulk refractory high-entropy alloys is governed primarily by chemically mediated defect energetics rather than grain-boundary sink density, providing a design strategy for advanced radiation-tolerant structural materials. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Nuclear Materials, Characterization, High-Entropy Alloys |