skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Thermodynamic studies and the phase diagram of the Li-Mg system

Journal Article · · Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science
DOI:https://doi.org/10.1007/BF02652335· OSTI ID:382495
; ;  [1];  [2]
  1. Polish Academy of Sciences, Krakow (Poland). Inst. of Metallurgy and Materials Science
  2. Univ. of Saarlandes, Saarbruecken (Germany). Inst. of Physical Chemistry

By means of the electromotive force (emf) method of concentration cells of the following scheme: Li (1)/LiCl-LiF (eut) or LiCi-KCl (eut)/Li-Mg (1) or Li (1)/LiCl-LiF (eut)/Li-Mg (s). Li activities for liquid and solid alloys at the (Mg), (Li), and (Mg) + (Li) two-phase region of the Li-Mg system were determined. Liquid alloys were examined at temperatures from 638 to 889 K at various Li concentrations. The (Mg) solid solutions were investigated in two series: at constant temperatures between 773 and 876 K, with varying Li content, and at fixed Li concentrations, equal to 0.125 and 0.160 molar fractions, at different temperatures between 772 and 849 K. At the two-phase region, (Mg) + (Li), emf measurements were performed in the temperature range 773 to 838 K, with fixed Li concentrations equal to 0.20, 0.25, and 0.275 molar fractions. For (Li) solid alloys, experiments were done at temperatures 773 to 849 K for several constant Li concentrations, between 0.30 and 0.45 molar fractions, respectively. Studies on solid alloys enabled the authors also to determine the boundaries (Li)/[(Mg) + (Li)] and (Mg)/[(Mg) + (Li)] at temperatures 773 to 831 K. The resulting thermodynamic and phase boundary data of this study were used with other selected references for a critical assessment of the Li-Mg system. The Lukas BINGSS optimization program and BINFKT for the calculation of the thermodynamic functions and of the phase diagram were used. The calculated equilibrium phase diagram at temperatures below 750 K indicates a slightly lower solid solubility of Mg in (Li) in comparison with results from thermal analysis and the recently published Saunders evaluation.

Sponsoring Organization:
USDOE
OSTI ID:
382495
Journal Information:
Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science, Vol. 27, Issue 9; Other Information: PBD: Sep 1996
Country of Publication:
United States
Language:
English