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Thermodynamic analysis of the topologically close packed ? phase in the Co-Cr system.

ABSTRACT: Density functional theory (DFT) calculations show that it is essential to consider the magnetic contribution to the total energy for the end-members of the ? phase. A more straightforward method to use the DFT results in a CALPHAD (Calculation of phase diagrams) description has been applied in the present work. It was found that only the results from DFT calculations considering spin-polarization are necessary to obtain a reliable description of the ? phase. The benefits of this method are: the DFT calculation work can be reduced and the CALPHAD description of the magnetic contribution is more reliable. A revised thermodynamic description of the Co-Cr system is presented which gives improved agreement with experimental phase boundary data for the ? phase.

SUBMITTER: Wang P

PROVIDER: S-EPMC6774197 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Thermodynamic analysis of the topologically close packed σ phase in the Co-Cr system.

Wang Peisheng P Peters Matthew C MC Kattner Ursula R UR Choudhary Kamal K Olson Gregory B GB

Intermetallics 20190101

Density functional theory (DFT) calculations show that it is essential to consider the magnetic contribution to the total energy for the end-members of the σ phase. A more straightforward method to use the DFT results in a CALPHAD (Calculation of phase diagrams) description has been applied in the present work. It was found that only the results from DFT calculations considering spin-polarization are necessary to obtain a reliable description of the σ phase. The benefits of this method are: the ...[more]

PMID: 31579354

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