Ab initio and thermodynamic study of the Cr-Re system
M. Palumbo, T. Abe, C. Kocer, H. Murakami, H. Onodera.
CALPHAD: Computer Coupling of Phase Diagrams and Thermochemistry, Elsevier Ltd., 34, 495-503, (2010)
In this work the assessment of the Cr–Re system, using a combined ab initio and CALPHAD (CALculation of Phase Diagrams) approach, is presented. To model the sigma phase, a five-sublattice combined CEF model was applied
and the present description reproduces reasonably well the previously published experimental phase diagram.
Formation enthalpies of the stable/metastable configurations of the sigma phase were estimated from ab initio calculations. A comparison of results using simplified two- and three-sublattice models and the five-sublattice
model for the sigma phase is also presented, which highlights differences in calculated properties as site occupan-
(Cr, Re)2 (Cr, Re)4 (Cr, Re)8 (Cr, Re)8 (Cr, Re)8 , based on Wyckoff positions, is necessary to reproduce the
atomic ordering in the sigma phase. Certain areas of the phase diagram still remain uncertain and deserve further experimental investigation.
Keyword(s): intermetallics; phase diagrams; enthalpy; thermodynamic modelling; ab initio calculations