About this Abstract |
Meeting |
MS&T24: Materials Science & Technology
|
Symposium
|
Austenite Formation and Decomposition V: A Symposium in Memory of Prof. Mats Hillert
|
Presentation Title |
Non-Equilibrium Interfaces during Phase Transformations |
Author(s) |
Chris Hareland, Edwin Antillon, Gildas Guillemot, Charles-Andre Gandin, Peter W. Voorhees |
On-Site Speaker (Planned) |
Peter W. Voorhees |
Abstract Scope |
A unified thermodynamic description of moving non-equilibrium interfaces is developed for both solid-solid and solid-liquid transformations. The theory is applicable to concentrated multicomponent alloys where diffusion is possible in both phases or in just the parent phase, and where energy is dissipated due to solute drag. To be consistent with energy dissipation, we find that solute drag affects both the velocity of the interface and interfacial distribution coefficients. For binary alloy solidification, the theory predicts significant changes in the interfacial compositions from that given by the equilibrium phase diagram at velocities commonly found during additive manufacturing. Molecular dynamics (MD) is used to determine the non-equilibrium interfacial properties. The partial-solute-drag model yields a trans-interface diffusivity much different from that of more classical models and very close to that measured in the MD simulations. A comparison to Matt Hillert's work on non-equilibrium interfaces during solid/solid phase transformations will also be given. |