About this Abstract |
Meeting |
2024 TMS Annual Meeting & Exhibition
|
Symposium
|
Computational Thermodynamics and Kinetics
|
Presentation Title |
Modeling the Nature of Suzuki Segregation with High Throughput Computational Techniques |
Author(s) |
Victoria Tucker, Michael Titus |
On-Site Speaker (Planned) |
Victoria Tucker |
Abstract Scope |
The fundamental driving forces for solute segregation to planar defects in superalloys are still not well understood. This work investigates the L12 γ ’ – forming Ni-Co-Al-X (X=Ta, Ti, Nb) alloys to better understand the segregation thermodynamics. D019 and D024 SISF-like structure’s Gibbs free energy curves which demonstrate positive inflection in the center with minima on either side are predicted to phase separate— determined by the common tangent reconstruction and the Suzuki Criterion. Density functional theory (DFT) special quasirandom structure calculations for the D019 and D024 structures are shown for each system. Finally, using DFT- VASP and CASM, a recently developed Bayesian-Global optimization method for predicting the energies of uncalculated configurations, and grand canonical Monte Carlo simulations SISF embedded supercells across the Ta composition space are calculated. This work reveals strong Ta segregation at compositions containing more than 7.5at% Ta and Ta depletion in alloys containing less than 5at% Ta. |
Proceedings Inclusion? |
Planned: |
Keywords |
High-Temperature Materials, Modeling and Simulation, Phase Transformations |