Physical properties of some Sn-based melts

The physical properties (viscosity, density, electroresistivity and magnetic susceptibility) of pure tin, copper, silver, some binary (Sn - Ag, Sn - Cu, Sn - Bi, Sn - Zn) and ternary (Sn-Ag-Cu, Sn-Bi-Ag, Sn-Bi-Zn) alloys with near eutectic compositions are investigated in wide temperature ranges. The irreversible decrease of viscosity in pure tin melt is discovered at 820 degrees C during heating. The similar anomaly with the following hysteresis of dynamic viscosity was fixed for binary and ternary alloys but at higher temperatures - 900 degrees C and 950 degrees C respectively. For all the systems it was shown that the alloys with eutectic compositions differ significantly in their electric and magnetic properties from hypo- and hypereutectic ones. Qualitative and quantitative metallographic analysis for Sn-3.8wt.%Ag-0.7wt.%Cu samples, heated low and above characteristic temperatures, showed the influence of melt overheating on crystallization kinetics.