THERMODYNAMIC PROPERTIES OF THE LIQUID Ag-Bi-Cu-Sn LEAD-FREE SOLDER ALLOYS

THERMODYNAMIC PROPERTIES OF THE LIQUID Ag-Bi-Cu-Sn LEAD-FREE SOLDER ALLOYS G. Garzel, M.Kopyto, L. A. Zabdyr Institute of Metallurgy and Materials Science, Polish Academy of Sciences, Laboratory of Physical Chemistry of Materials, Krakow, Poland (Received 27 July 2013; accepted 02 April 2014) The electromotive force measurement method was employed to determine the thermodynamic properties of liquid Ag-Bi-Cu-Sn alloys using solid electrolyte galvanic cells as shown below: Kanthal+Re, Ag-Bi-Cu-Sn, SnO2 vertical bar Yttria Stabilized Zirconia vertical bar air, Pt, Experiments were made within temperature interval: 950-1300K along four composition paths of constant ratios: [GRAPHICS] and tin concentration changing from 0.110 0.9 mole fractions, every 0.1. Atmost all the results were approximated by straight line equations: EMF vs T, and tin activities were then calculated in arbitrary temperature; measurement results were presented by graphs. Unusual activity plot for X-B1: (X-Ag + X-Cu) = 3:2 composition path was most probably caused by miscibility gap detected earlier in Bi-Cu-Sn ternary liquid alloys.