Direct Activity Measurements in Liquid Ag-Au=Ge System and its Solution Model Development by Computational Techniques

Abstract

Ag activities in the Ag-Au-Ge solution were determined by the mass spectrometric analysis of effusates from a unique valved Knudsen cell at 1416 K. A mathematical model was established for Ag activity coefficient as a function of alloy composition. Activities of Au and Ge were calculated by numerical ternary Gibbs-Duhem integration on a spreadsheet. The data obtained from this investigation show that the activities on all three binary systems occurring in the ternary system are in good agreement with accepted literature values. The behavior of all pseudo binaries was found to be consistent with Darken's quadratic formalism. Darken surface of Ag is shown.