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

• Published in: Journal of phase equilibria and diffusion 2019-02, Vol.40 (1), p.115-125
• Main Authors: Delsante, Simona, Borzone, Gabriella, Novakovic, Rada
• Format: Article
• Language: English
• Subjects: Alloys; Calibration; Ceramics; Chemistry; Composites; Copper; Copper base alloys; Correlation analysis; Crystallography and Scattering Methods; Engineering Thermodynamics; Eutectic alloys; Glass; Heat; Heat and Mass Transfer; High temperature; Mechanical properties; Melt temperature; Metallic Materials; Natural Materials; Physics; Physics and Astronomy; Scanning electron microscopy; Silver base alloys; Solders; Sterling; Subsystems; Surface properties; Surface tension; Thermodynamic properties; Thermodynamics; Wetting
• ISSN: 1547-7037; 1863-7345; 1934-7243
• DOI: 10.1007/s11669-019-00709-z

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.