Phase Equilibria of the Sn-Sb-Ag Ternary System (I): Experimental

The Sn-Sb-Ag system is of interest to the electronics industry. However, only limited Sn-Sb-Ag phase equilibria information is available and the Sn-Sb-Ag liquidus projections in the literature are not consistent. The 250 C isothermal section and the liquidus projection of the ternary Sn-Sb-Ag system are experimentally determined in this study. No ternary compounds are found. Two continuous solid solutions, epsilon and zeta phases, are formed between epsilon-Ag3Sn and epsilon-Ag3Sb, and zeta-Ag17Sb3 and zeta-Ag5Sn, respectively. There are three tie-triangles, L + Sn3Sb2 + epsilon, Sn3Sb2 + beta-SnSb + epsilon, and beta-SnSb + Sb + epsilon, in the 250 C Sn-Sb-Ag isothermal section. The solubilities of Ag in the Sn3Sb2, beta-SnSb, and Sb phases at 250 C are very small. There are three ternary invariant reactions. The reaction temperatures are 379 C, 314 C, and 233 C for the L + Sb = beta-SnSb + epsilon, L + beta-SnSb = Sn3Sb2 + epsilon, and L + Sn3Sb2 = epsilon + Sn, respectively.