|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Computational Thermodynamics and Kinetics
||General Method for Incorporating CALPHAD Free Energies of Mixing into Phase Field Models: Application to the α-Zirconium/δ-Hydride System
||Andrea Jokisaari, Katsuyo Thornton
|On-Site Speaker (Planned)
We present a general method of incorporating CALPHAD-based free energies into a phase field model. While CALPHAD-based free energy descriptions provide realistic energetics of alloys, their formulations pose numerical difficulties for phase field simulations because the free energies of mixing are only defined over a finite concentration range of solute and their derivatives exhibit highly nonlinear behavior. In addition, free energies of mixing for different phases are not necessarily defined over the same concentration ranges. The method presented approximates the free energies of mixing using piecewise functions to eliminate the aforementioned characteristics while largely retaining the free energy values and the first and second derivative information, which also affect the thermodynamic and kinetic behavior of the system. The method has been implemented and used to examine hydride precipitation and microstructure formation.
||Planned: A print-only volume