Microstructure and Mechanical Property of Sn-Bi+Nano Graphite Composite Solder
Sn-Bi solder alloy was modified by nano-graphite. The mechanical properties of the composite solder alloy joints were investigated by micro mechanical tester. The microstructure and fracture were studied by SEM. The results show that the microstructure of the solder alloy is refined gradually with the content of nano graphite increasing. The ultimate tensile strength of the welded joint decreases with the addition of nano graphite. The elongation of the welded joint improves with the addition of nano-graphite. The mechanical property of the solder joint is well when the fraction of nano graphite is 0.07 wt%.