| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Mechanical Response of Materials Investigated Through Novel In-Situ Experiments and Modeling
|
| Presentation Title |
Real-time sub-microscopic observation and atomic simulation of deformation-induced martensitic transformation at grain boundaries |
| Author(s) |
Jesada Punyafu, Tomotsugu Shimokawa, Myeong-heom Park, Nobuhiro Tsuji, Mitsuhiro Murayama |
| On-Site Speaker (Planned) |
Jesada Punyafu |
| Abstract Scope |
Deformation-induced martensitic transformation enables high strength and large ductility in steels. Although this phenomenon has been extensively studied, the influence of grain boundary characteristics is still under discussion. This study investigates martensite nucleation from grain boundaries during plastic deformation in an ultrafine-grained Fe-24Ni-0.3C (wt. %) metastable austenitic steel using in situ transmission electron microscopy mechanical testing. Real-time sub-microscopic observations have revealed that grain-boundary triple junctions are preferred nucleation sites for martensitic transformation. The experimental results combined with crystallographic information of individual grains provided ground for setting up realistic structure models to implement subsequent computational investigation. Molecular dynamics simulations further demonstrated the dominant factors dictating the nucleation including the misorientation angle between martensite variants and the transformation strain components. The comparison between experimental and simulation results generating new hypotheses for further validation will be discussed. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Phase Transformations, Characterization, Modeling and Simulation |