Thermodynamic Modeling of the Al-Ba and Ba-Ge Systems Supported by First-Principles Calculations

Benhafid R., Bouzida A. B., Djaballah Y., Candan A., Iyigor A., UĞUR G.

JOURNAL OF PHASE EQUILIBRIA AND DIFFUSION, vol.40, no.2, pp.195-205, 2019 (SCI-Expanded, Scopus) identifier identifier

  • Publication Type: Article / Article
  • Volume: 40 Issue: 2
  • Publication Date: 2019
  • Doi Number: 10.1007/s11669-019-00714-2
  • Journal Name: JOURNAL OF PHASE EQUILIBRIA AND DIFFUSION
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.195-205
  • Keywords: Al-Ba alloys, Ba-Ge alloys, CALPHAD, first-principles calculation, phase diagram, thermodynamics, TOTAL-ENERGY CALCULATIONS, CRYSTAL-STRUCTURE, INTERMETALLIC COMPOUNDS, PHASE-DIAGRAM, ALUMINUM, CLATHRATE, RICH
  • Gazi University Affiliated: Yes

Abstract

The phase diagrams of Al-Ba and Ba-Ge systems are optimized by coupling the CALPHAD approach and first-principles calculations. The binary intermetallic compounds were treated as stoichiometric phases. The total energies of nine intermetallic compounds: Al4Ba, Al13Ba7, Al5Ba3, Al5Ba4, Ba2Ge, Ba5Ge3, BaGe, -Ba3Ge4 and BaGe2 were calculated by first-principles calculation using density functional theory approximation as implemented in the VASP (Vienna Ab-initio Simulation Package) code and used in the CALPHAD approach to assess the two systems. The liquid solutions are described by the Redlich-Kister polynomial model. A set of thermodynamic parameters were obtained for the Al-Ba and Ba-Ge systems. The calculated phase diagrams and thermodynamic properties are in good agreement with most of the accuracy available data.