Experimental study of the Ag-Sn-In phase diagram

Combined metallographic, differential scanning calorimetry, X-ray and scanning electron microscopy studies have been performed using 27 ternary alloys. The microhardness of the alpha(Ag), epsilon(Ag3Sn) and zeta(Ag4Sn,Ag3In) phases has been measured. The ternary extension of the phase phi(AgxInySnz, where x approximate to 0.36, y approximate to 0.61, z approximate to 0.03) has been revealed in some specimens, although the binary compound (AgIn2) melts at 166 degrees C. This finding is attributed to the limited cooling rate. The solubility ranges of the solid solution and the intermetallic phases have been determined. The tin and the indium show approximately equal mutual solubility (around 2 at.%) in the ternary extensions of their Ag-Sn or Ag-In phases. The experimental data have been compared with a calculated isothermal section at 280 degrees C and with a vertical section at 2.5 at.% Ag. The thermal analyses have confirmed, in general, the temperatures of the invariant reactions in the Ag-Sn-In system as calculated by literature data. (c) 2005 Elsevier B.V. All rights reserved.