The study of Sn-45Bi-2.6Zn alloy before and after thermal aging

Abstract

A new Sn-45Bi-2.6Zn (wt. %) alloy was developed to replacing eutectic Sn-58Bi alloy as a low-melting temperature solder alloy. A tensile elongation improvement was obtained by increasing the Sn to Bi volume ratio because the content of intrinsic brittle Bi was reduced. A solidus temperature of 133 Υ was achieved in a calculated Sn-Bi-Zn ternary system. The calculation of phase diagram (CALPHAD) method was used to help understand the melting behavior of Sn-45Bi-2.6Zn alloy. After aging, the elongation was still superior than that of eutectic Sn-58bi owing to the larger volume fraction of Sn phase.