|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Computational Thermodynamics and Kinetics
||First-principles/Phase-field Modeling of Equilibrium θ^' Precipitation in Al-Cu Alloys
||Kyoungdoc Kim, M. P. Gururajan, C. Wolverton, P. W. Voorhees
|On-Site Speaker (Planned)
The growth of equilibrium Al2Cu (θ^') morphology in Al-Cu alloys is examined using a phase field method with the parameters supplied by first-principles methods. The phase field method allows for an interfacial energy that is highly anisotropic: there are missing orientations and corners on the Wulff shape. This yields a plate-shaped equilibrium θ^' precipitate. Also, we consider the effects of a mismatch in elastic-moduli (elastic inhomogeneity) of Al and θ^', as well as tetragonal misfit strain anisotropy. The results show that the aspect ratio of a precipitate with the anisotropy of interfacial and strain energy as given by the first-principles methods is significantly smaller than the equilibrium aspect ratio observed in the experiment. Specifically, the computed equilibrium aspect ratio of the particle morphology is almost ten-times smaller than the aspect ratio observed in experiment. We conclude that the experimental equilibrium morphology is strongly influenced by the kinetics of particle growth.
||Planned: Supplemental Proceedings volume