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The maximum bubble pressure method has been used to measure the surface tension of pure antimony and the surface tension and density (dilatometric method) of Sn-3.8 at%Ag eutectic base alloys with 0.03, 0.06 and 0.09 molar fraction of antimony at a temperature range from 550 to 1200 K. The linear dependencies of surface tension and density on temperature were observed and they were described by straight-line equations. Moreover, experimental determination of phase diagram and thermodynamic calculations in the Sn-Ag-Sb system were performed and the resulting optimized thermodynamic parameters were used for modeling of the surface tension. In addition, a non-equilibrium solidification process using the Scheil model was simulated and compared with the equilibrium solidification behavior of a Sn-Ag-Sb alloy.

The morphologies and growth of "(Cu 3 Sn) and (Cu 6 Sn 5 ) intermetallic compounds (IMCs) between a molten Sn base solder and a Cu substrate were experimentally investigated. It is shown that the thickness of the "(Cu 3 Sn) and (Cu 6 Sn 5 ) compounds decreases with deceasing Sn content and that the order of the growth rate of the compounds on the Cu substrate are as follows: Sn-57(mass%)Bi < Sn-37Pb < Sn-3.5Ag < Sn < Sn-6.7Sb. The growth of these phases basically obeys the parabolic law, but the growth behavior is divided into two stages, the growth rate and morphology of the (Cu 6 Sn 5 ) compound are differing from each other in the two-stage. It is suggested that the grooving effect is at least one of the origins of the formation of the scallop morphology of the (Cu 6 Sn 5 ) compound.

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The phase equilibria of the In-Ag-Bi and In-Ag-Sb systems were determined by differential scanning calorimetry (DSC) and electron probe microanalysis (EPMA). Thermodynamic calculations of these systems were also carried out by taking the experimental results into account. The Gibbs energies of the liquid and solid solution phases are described on the basis of the sub-regular solution model, and that of the intermetallic compounds are based on the two-sublattice model. A consistent set of thermodynamic parameters was optimized for describing the Gibbs energy of each phase, which leads to a good fit between calculated and experimental results. In addition, the surface tension and viscosity of liquid phase were calculated on the basis of the thermodynamic parameters obtained in the present assessment.