|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Computational Thermodynamics and Kinetics
||First-principles Calculations of Bulk and Interfacial Thermodynamic Properties for Al-Li and Al-Cu-Li Alloys
||Bi-Cheng Zhou, Kyoungdoc Kim, Christopher Wolverton
|On-Site Speaker (Planned)
Al-Li and Al-Cu-Li based alloys offer attractive properties: low density, high elastic modulus, and high specific strength, which are ideal for aerospace structural applications. The high strength of these alloys is largely attributed to precipitation hardening of δ’ (Al3Li) and T1 phases. First-principles calculations based on density functional theory have been used to understand bulk and interfacial thermodynamics of precipitates in Al-Li and Al-Cu-Li alloys. A cluster expansion of alloy energetics was constructed for fcc- and bcc-based Al-Li alloys, which includes both the configurational and vibrational entropic contributions to free energy. Finite-temperature bulk and interfacial thermodynamic properties of δ’ and T1 phases were calculated. A newly proposed crystal structure of T1 phase based on first-principles energetics was used in this study. Different terminations of T1 phase with respect to Al (111) plane were examined. This work shed light on the phase stability of important precipitate phases for aerospace alloy design.
||Planned: Supplemental Proceedings volume