Thermodynamic properties of calcium–magnesium alloys determined by emf measurements
نویسندگان
چکیده
The thermodynamic properties of calcium–magnesium alloys were determined by electromotive force (emf) measurements using a Ca(in Bi)|CaF2|Ca(in Mg) cell over the temperature range 713–1048 K. The activity and partial molar Gibbs free energy of calcium in magnesium were calculated for nine Ca–Mg alloys, calcium mole fractions varying from xCa = 0.01 to 0.80. Thermodynamic properties of magnesium in calcium and the molar Gibbs free energy of mixing were estimated using the Gibbs–Duhem relationship. In the all-liquid region at 1010 K, the activity of calcium in magnesium was found to range between 8.8 × 10−4 and 0.94 versus pure calcium. The molecular interaction volume model (MIVM) was used to model the activity coefficient of Ca and Mg in Ca–Mg liquid alloys. Based on this work, Ca–Mg alloys show promise as the negative electrode of a liquid metal battery in which calcium is the itinerant species: alloying with Mg results in both a decrease in operating temperature and suppression of Ca metal solubility in the molten salt electrolyte. © 2012 Elsevier Ltd. All rights reserved.
منابع مشابه
Thermodynamic Measurements on Alloys and Compounds in Ag-Au-Se and Ag-Pd systems by the Electromotive Force Method
Aalto University, P.O. Box 11000, FI-00076 Aalto www.aalto.fi Author Dawei Feng Name of the doctoral dissertation Thermodynamic Measurements on Alloys and Compounds in Ag-Au-Se and Ag-Pd systems by the Electromotive Force Method Publisher School of Chemical Technology Unit Department of Materials Science and Engineering Series Aalto University publication series DOCTORAL DISSERTATIONS 172/2014 ...
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