| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advances in Multi-Principal Element Alloys IV: Mechanical Behavior
|
| Presentation Title |
Damage Tolerance in bcc vs. fcc High-Entropy Alloys |
| Author(s) |
Robert O. Ritchie, Andrew M. Minor, Mark Asta, Punit Kumar, David Cook, Madelyn Payne, Wenqing Wang, Pedro P.P.O. Borges |
| On-Site Speaker (Planned) |
Robert O. Ritchie |
| Abstract Scope |
Face-centered cubic (fcc) medium- and high-entropy alloys (HEAs) can display exceptional combinations of strength, tensile ductility and fracture toughness, properties that can be further enhanced at cryogenic temperatures. Body-centered cubic (bcc) refractory RHEAs, conversely, can display exceptional strength and compressive ductility at elevated temperatures, but are often compromised by poor lower-temperature behavior. We examine here the damage-tolerance of these two classes of multiple principal-element alloys, and show that whereas some of the fcc HEAs exhibit among highest toughness values on record, even under extreme conditions of ultrahigh strain rates and liquid-helium temperatures, the bcc HEAs can display extremely low toughness when subject to tensile loading. We explore the reasons for such distinct properties, and investigate why most bcc HEAs are markedly brittle, whereas a few, such as NbTaTiHf, can display remarkably high toughness. We further examine the role of short-range order and indicate its possible mechanistic relevance to damage tolerance. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Mechanical Properties, High-Entropy Alloys, High-Temperature Materials |