About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advances in Multi-Principal Element Alloys V: Mechanical Behavior
|
| Presentation Title |
Achieving Deformation-Induced Nano-sized Twins and hcp Structures in FCC Complex Concentrated Alloys Under Charpy Impact Testing |
| Author(s) |
Hrishikesh Deodhar, Hyunseok Oh |
| On-Site Speaker (Planned) |
Hrishikesh Deodhar |
| Abstract Scope |
Although twin and martensite structures contribute to strain hardenability, their formation often reduces the damage tolerance of alloys under harsh conditions. Therefore, refining coarse twin and martensite structures into nano-sized hcp and twin structures has been actively investigated, particularly in FCC complex concentrated alloys (CCAs) with low stacking fault energies (SFEs). In this study, we observed that achieving such refinement of hcp/twin structures is significantly more challenging under Charpy impact testing than in tensile testing, across temperatures ranging from room temperature down to cryogenic conditions, for various low-SFE CCAs (e.g., Co-rich CCAs). In this presentation, we discuss the origins of this difference and propose alloy composition modifications to promote the formation of nano-sized hcp and twin structures, leveraging the effects of short-range ordering. This approach provides alloy design pathways for enhancing critical damage tolerance in CCAs under cryogenic temperatures. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
High-Entropy Alloys, Phase Transformations, Mechanical Properties |