Effect of adding nanometric ZnO particles on thermal, microstructure and tensile creep properties of Sn-6.5 wt%Zn-3 wt%In solder alloy

Abstract

Mechanical properties of solders benefit from uniform dispersion of fine precipitates and small effective grain sizes. Metallurgical methods of attaining such a beneficial microstructure have been investigated in the plain Sn-6.5 wt%Zn-3 wt%In (plain) solder and Sn-6.5 wt%Zn-3 wt%In-0.3 wt%ZnO (composite) solder. It has been found that a small alloying addition of ZnO nano particles has a beneficial effect on the microstructure. It improves the tensile creep properties of the composite solder alloy. The improvement is attributed to uniform distribution and refining of the beta-Sn dendrites and the effective refined grain size in the solidified microstructure. Thereby the composite solder has better mechanical properties than the plain solder alloy.