| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
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| Symposium
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Recent Advances in Titanium Science and Technology: MPMD/SMD Symposium Honoring Professor Dipankar Banerjee
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| Presentation Title |
Structure and mobility of deformation twin boundaries in ferroelatic crystals |
| Author(s) |
Yuchi Wang, Hao Tang, Ju Li, Yunzhi Wang |
| On-Site Speaker (Planned) |
Yunzhi Wang |
| Abstract Scope |
The core structures of crystalline defects are crucial for determining their thermodynamic and kinetic behaviors that impact the mechanical and functional properties. Recent studies revealed extended core structures of deformation twin boundaries in metastable beta-Ti alloys and NiTi shape memory alloys (SMAs). Using molecular dynamics (MD) simulations, we characterized the {114}_B2 deformation twin boundary in the B2 phase of NiTi SMA. Unlike conventional sharp twin boundaries, we found gently curved atomic planes across the boundaries. This distinctive extended core structure allows twin boundary motion under load without a stress threshold. Close structure examination and deformation pathway analysis indicate these boundaries consist of a “wetting” B19’ martensitic phase. The MD simulation suggests a close coupling between deformation and martensitic transformation that facilitates twin boundary motion, eliminating the need for nucleating partial dislocations. This study may provide insights into the unique properties of these alloys after cold-working, prompting future experimental investigations. |
| Proceedings Inclusion? |
Planned: |