EFFECT OF BISMUTH CONTENT ON MICROSTRUCTURE, MELTING TEMPERATURE AND UNDERCOOLING OF SN-0.7CU SOLDER ALLOY

Abstract

The aim of this manuscript to study the influence of Bismuth (Bi) addition on the microstructure, melting temperature and undercooling of Sn-0.7Cu solder alloys. In this study, several Bi composition were chosen which is 0 wt.%, 0.25 wt.%, 0.5 wt.%, 1.0 wt.% and 2.0 wt%. The result indicated that with addition of Bi element, it can refine the β-Sn and reduce the size of primary Cu6Sn5. The melting temperature of Sn-0.7Cu solder alloy was observed by DSC result and found there is no significant changes of melting temperature by Bi additions. However, with Bi addition, it will reduce the undercooling of the Sn-0.7Cu solder alloys