Effects of Al on the failure mechanism of the Sn-Ag-Zn eutectic solder

摘要

Tensile testing of Sn-3.7Ag-0.9Zn-xAl (x = 0,0.5 and 1.0 wt.%) solders have been performed and the failure mechanism was investigated. The results suggest that the addition of Al in the Sn-3.7Ag-0.9Zn solder decreases both the tensile strength and ductility. Moreover, a brittle fracture occurs instead of a ductile fracture with increasing Al content. The fractographs suggest that the fracture mechanism of Sn-Ag-Zn eutectic solder is microvoid coalescence fracture, and the Sn-3.7Ag-0.9Zn-xAl (x=0.5 and 1.0) solder corresponds to quasi-cleavage crack and cleavage fracture respectively.