About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advanced Characterization Techniques for Quantifying and Modeling Deformation
|
| Presentation Title |
Twinning Interfaces- Addressing Key Issues |
| Author(s) |
Daegun You, Ahmed Sameer Khan Mohammed, Minoru Nishida, Huseyin Sehitoglu |
| On-Site Speaker (Planned) |
Daegun You |
| Abstract Scope |
Experimental evidence of Type-I{111} twinning is prevalent in NiTi alloys. This is unexpected because Type-I{011} is the conjugate twin system to Type-II<011> that should be prevalent instead. The possible reason for the prevalence of Type-I{111} has not been explained. This study calculates the twin-boundary energies for both type of twins and found that Type-I{111} is favored over Type-I{011} because the twin-boundary energies are much lower. This requires DFT calculations because MD potentials miss the positioning of the lattice-motif points. Such a calculation also requires energy-minimization at the boundary to allow lattice-offsets. With the correct-offsets, further shear and shuffles establish twin-migration barriers that illustrate a preference for Type-I{111}. The results are compared to HRTEM positioning of NiTi atoms that precisely match Type-I{011} simulations results. The implication of the results in transforming materials are discussed as well as the complex interfaces that develop as a result of both Type-II and Type-I intersections. |
| Proceedings Inclusion? |
Planned: |