About this Abstract |
| Meeting |
2027 TMS Annual Meeting & Exhibition
|
| Symposium
|
Progress Toward Mechanisms, Thermodynamics, and Kinetics of Phase Transformations: An MPMD/SMD Symposium Honoring John H Perepezko
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| Presentation Title |
Interface-mediated phase selection during mechanical alloying of Ni-Si alloys |
| Author(s) |
Rudraksha Bhardwaj, Pratik K Ray |
| On-Site Speaker (Planned) |
Rudraksha Bhardwaj |
| Abstract Scope |
Phase selection during mechanical alloying is often governed by kinetic pathways that bypass equilibrium phases. However, a unified thermodynamic framework to predict these transitions remains unexplored. In this study, we examine the competition between stable and metastable phases in the Ni-Si system. Five specific compositions were synthesized via high-energy ball milling to understand phase selection mechanisms. A theoretical framework that uses the solid-solid interfacial energy (γS/S) for phase selection in the nanocrystalline regime was created. Interfacial energies were calculated using a mathematical model and MD simulations. By integrating these values into Classical Nucleation Theory and conducting a probabilistic analysis, we explained the dependence of the nucleation barrier in bypassing phases under non-equilibrium conditions. Experimental validation via XRD and HRTEM confirmed the bypassing of equilibrium phases and favoured the non-equilibrium metastable phases. Our findings provide a complete thermodynamic framework for predicting phase evolution in nanocrystalline systems using interfacial energetics. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Phase Transformations, Modeling and Simulation, Characterization |