Effect of graphene nanosheets on the corrosion behavior of Sn–Ag–Cu solders

In this study, the effect of graphene nanosheets (GNSs) on the corrosion resistance of 96.5Sn–3Ag–0.5Cu (SAC) solder at ambient temperature in a 3.5 wt% NaCl solution was investigated using the potentiodynamic polarization method . The corrosion products were analyzed by field emission-scanning electron microscope, energy dispersive spectroscopy , and X-ray diffraction. The results showed that the GNSs affect the anodic polarization behavior of the solders. Adding GNSs enhanced the corrosion resistance of the SAC solder, as GNSs content increased to 0.03 wt%, the corrosion resistance peaked and then declined with further increment in the wt% of the GNSs. Overall, the corrosion resistance of SAC/GNSs was found to be more superior than that of the pure SAC. The mechanism of the corrosion resistance improvement can be explained by the formation of a compact corrosion layer of the GNSs. This provides an inert physical barrier to the initiation and development of corrosion. As the GNSs content further increased (more than 0.03 wt%), the corrosion resistance of the SAC/GNSs solder decreased.