Journal of Phase Equilibria and Diffusion

, Volume 40, Issue 1, pp 115–125 | Cite as

Experimental Thermodynamics and Surface Properties of Ag-Cu-Ge Solder/Braze Alloys

  • Simona Delsante
  • Gabriella Borzone
  • Rada NovakovicEmail author


Ag-based alloys have industrial importance in relation to their use as high-temperature solders in jewellery or braze alloys for thermoelectric modules. Good wetting properties and a tarnish-resistance of Ag-Ge and Ag-Cu-Ge alloys together with appropriate mechanical properties make them good candidates for bonding sterling silver (Ag-7.5Cu, in wt.%). The melting temperature and the heat of melting of Ag-Cu, Ag-Ge and Ag-Cu-Ge eutectic alloys have been measured by differential scanning calorimetry. From a technological point of view, particular attention should be paid to the surface tension, a key property of the joining processes. The aim of this study is to correlate the thermodynamic properties of the Ag-Cu-Ge system and its subsystems with their surface properties and to compare the model predicted property values to the data available in the literature.


Ag-Cu-Ge alloys Butler’s model calorimetry surface tension thermodynamic modeling 



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Copyright information

© ASM International 2019

Authors and Affiliations

  • Simona Delsante
    • 1
    • 2
  • Gabriella Borzone
    • 1
    • 2
  • Rada Novakovic
    • 2
    Email author
  1. 1.Department of Chemistry and Industrial ChemistryGenoa University and Genoa Research Unit of INSTMGenoaItaly
  2. 2.Institute of Condensed Matter Chemistry and Energy TechnologiesNational Research Council (ICMATE-CNR)GenoaItaly

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