First Principles Prediction of the Al-Li Phase Diagram
نویسندگان
چکیده
The phase diagram of the Al-Li system was determined by means first principles calculations in combination with cluster expansion formalism and statistical mechanics. ground state phases were from fcc bcc configurations whole compositional range, while transitions as a function temperature ascertained thermodynamic grand potential Gibbs free energies phases. Overall, calculated good agreement currently accepted experimental diagram, but simulations provided new insights that are important to optimize microstructure these alloys heat treatments. In particular, structure GP zones, made up Al0.5Li0.5 (001) monolayers embedded Al matrix, identified. It found Al3Li is stable although energy barrier for transformation into AlLi very small (a few meV) can be overcome thermal vibrations. Moreover, formed martensitic precipitates stand favorable sites nucleation because they contain basic blocks such ordering. Finally, polynomial expressions different composition given, so used mesoscale precipitation alloys.
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ژورنال
عنوان ژورنال: Metallurgical and Materials Transactions
سال: 2021
ISSN: ['1073-5623', '1543-1940']
DOI: https://doi.org/10.1007/s11661-021-06419-x