Phase Equilibria in the System Ag-Ni-Sn: Thermal Behavior

The phase equilibria in the ternary Ag¿Ni¿Sn system, which has high relevance in lead-free soldering, were investigated by means of thermoanalytical methods. Together with the results of an earlier investigation by X − ray powder diffraction and electron probe microanalysis (Schmetterer et al., J Electron Mater, 2007), a complete and consistent ternary phase diagram was derived. Nine isopleths, a full liquidus projection and the corresponding reaction scheme (Scheil diagram) are presented here. Altogether eight invariant reactions involving the liquid phase were identified, i.e. two ternary eutectics (Type I reactions) and six transition reactions (Type II reactions), and the extension of the liquid miscibility gap was determined.