| About this Abstract |
| Meeting |
TMS Specialty Congress 2024
|
| Symposium
|
Accelerating Discovery for Mechanical Behavior of Materials 2024
|
| Presentation Title |
Investigating the Nucleation and Growth of Deformation Twinning in HfNbTaTi Refractory High Entropy via a Machine Learned Interatomic Potential
|
| Author(s) |
Wenqing Wang, Madelyn Payne, Pedro Borges, David Cook, Punit Kumar, Mark Asta, Robert Ritchie |
| On-Site Speaker (Planned) |
Wenqing Wang |
| Abstract Scope |
Refractory high-entropy alloys (RHEA) are characterized by high strength and compressive ductility at elevated temperatures. However, their practical application is hindered by brittle failure modes when subjected to tension at ambient temperatures. The plastic deformation behavior of RHEAs is closely tied to the energetics of deformation twinning, a well-known plasticity mechanism in refractory elements at low temperatures (below room temperature). In the HfNbTaTi alloy, abundant twinning is observed across a broad temperature range from 77 K to 1073 K, potentially playing a pivotal role in its mechanical properties. Recognizing its significance and the current knowledge gap regarding deformation twinning in HfNbTaTi RHEA, we explore the nucleation and growth of deformation twinning using a machine-learned atomic cluster expansion (ACE) potential. Our findings reveal a layer-by-layer growth pattern of deformation twins initiating from a 2-layer twin embryo, characterized by a near-isosceles equilibrium twin boundary structure. |
| Proceedings Inclusion? |
Definite: Other |