Compared study on properties of SnZn-based lead free solders

The wettability,creep resistance and mechanical properties of four SnZn-based solders were compared. Base on the wetting-balance test,the wettability of SnZnAg/SnZnGa/SnZnAl is better than SnZn solders. The addition of alloying elements can improve the wettability of SnZn alloys. With the testing of nanoindentation creep behavior of SnZn solders,it is found that the creep resistance of SnZnAg solder is highest of all, the mechanism is Ag-Zn particles acting as barriers to the motion of dislocations. In addition,with the testing of mechanical properties,the results show that the mechanical and thermal-fatigue resistance properties can be enhanced with the addition of alloying elements,the mechanical properties of SnZnAg solder joints is 20% higher than that of SnZn solder joints,the function of Ga/Al is less than Ag. Furthermore,using diode laser soldering,the mechanical properties of SnZn solder joints can increase up to 116.7%.