Thermodynamics Research Center, ThermoML : Thermochimica Acta

Experimental thermodynamics, surface and transport properties of liquid Ag-Ge alloys

Delsante, S.[Simona], Borzone, G.[Gabriella], Novakovic, R.[Rada]
Thermochim. Acta 2019, 682, 178432
ABSTRACT
The aim of this study is to correlate the thermodynamics of liquid Ag-Ge alloys with their thermophysical properties such as the surface tension, viscosity, electrical resistivity and microscopic functions. For this purpose the Quasi-Chemical Approximation (QCA) for the regular solution and Faber-Ziman theory have been applied to describe the mixing behaviour of Ag-Ge melts in terms of the energetics and structure. Concerning the Ag-Ge system, the most important is Ag-24.5Ge (in at %) eutectic alloy, widely used as a brazing filler material. The melting temperature and the heat of melting of Ag-Ge eutectic alloy were measured by Differential Scanning Calorimetry (DSC). From a technological point of view, particular attention should be paid to the surface tension, a key property of the joining processes. Accordingly, the QCA and Butler s model calculations have been done and subsequently, the model predicted values were compared to available literature data.
Compounds
# Formula Name
1 Ag silver
2 Ge germanium
Datasets
The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type Compound-# Property Variable Constraint Phase Method #Points
  • POMD
  • 1
  • 2
  • Eutectic temperature, K ; Crystal - 1
  • Crystal - 1
  • Crystal - 2
  • Liquid
  • Air at 1 atmosphere
  • DTA
  • 1
  • POMD
  • 1
  • 2
  • Eutectic composition: mole fraction - 2 ; Crystal - 1
  • Crystal - 1
  • Crystal - 2
  • Liquid
  • Air at 1 atmosphere
  • Derived from phase diagram analysis
  • 1