| About this Abstract |
| Meeting |
6th World Congress on Integrated Computational Materials Engineering (ICME 2022)
|
| Symposium
|
6th World Congress on Integrated Computational Materials Engineering (ICME 2022)
|
| Presentation Title |
First Principles Prediction of Al-Cu, Al-Li and Al-Cu-Li Phase Diagrams |
| Author(s) |
Sha Liu, Wei Shao, Javier Llorca |
| On-Site Speaker (Planned) |
Sha Liu |
| Abstract Scope |
A strategy is presented to predict the phase diagram of metallic alloys by means of first principles calculations in combination with the cluster expansion formalism and statistical mechanics. The ground state phases for each alloy were determined from first principles calculations of the different lattice configurations in the whole compositional range. In addition, the contribution of lattice vibrations to the free energy was included in the cluster expansion by a bond stiffness vs. bond length relationship obtained from the length-dependent transferable force constants. This information was used to fit a cluster expansion Hamiltonian which was used to determine the partition function and thermodynamic grand potential of each phase by means of Metropolis Monte Carlo simulations. Thus, the phase transitions as a function of temperature were ascertained from the thermodynamic grand potential and the Gibbs free energies of the phases. The strategy was applied to determine the phase diagram of Al-Cu, Al-Li, Al-Cu-Li alloys and the computed phase diagrams were compared with the current experimental phase diagrams in the literature. Overall, the calculated phase diagrams were in good agreement with the currently accepted experimental phase diagrams and, moreover, they provided new insights and information that is sometimes missing in the experimental phase diagrams due to the limitations imposed by the kinetics of phase changes. This additional information can be very important to optimize microstructure of these alloys by means of heat treatments. |
| Proceedings Inclusion? |
Definite: Other |