▎ 摘　　要

Graphene nanosheets (GNSs) of different mass fractions (Owt%, 0.025wt%, 0.05wt%, 0.075wt%, 0.1wt%, and 0.2wt%) were added into the Sn-58Bi low-temperature solder. The influences of GNSs on melting characteristics, wettability, shear properties, microstructure and interfacial reaction were investigated. Results show that adding GNSs has the positive effect on the wettability and shear strength of Sn-58Bi solder joint, and a slight influence on the melting temperature. After the addition of GNSs, a finer microstructure of Sn-58Bi solder is obtained. The thickness of intermetallic compound (IMC) at solder/Cu interface reduces significantly and the IMC morphology becomes flat after adding GNSs. In addition, with the addition of GNSs, the shear fracture mode of Sn-58Bi low-temperature solder converts from brittle into a mixed mode of brittle and ductile fracture, which is coincident with the changing situation of shear strength. In general, adding GNSs may be conducive to the improvement of solder joint reliability.