Effect of Sn-Decorated MWCNTs on the Mechanical Reliability of Sn-58Bi Solder

The mechanical reliability of Sn-MWCNT composite solder containing various content of Sn-decorated MWCNTs (0, 0.05, 0.1, and 0.2 wt%) and Sn-58Bi solder were investigated. The Sn-decorated MWCNTs nanoparticles were used to improve the mechanical reliability of Sn-58Bi solder, which is a representative, low-temperature, lead-free solder. The Sn-decorated MWCNT nanoparticles were synthesized using the polyol method, and the Sn-MWCNT composite solder paste was fabricated by mechanical mixing. The shear and bending tests were conducted to evaluate the mechanical properties of the solder joints. We identified the microstructure of solder to investigate the intermetallic compound and failure mechanism of Sn-MWCNT composite solder. Furthermore, a high-temperature storage test at 100 degrees C for 1000 h was performed to determine long-term reliability. The shear strength and fracture energy increased about 21% and 23%, respectively, with 0.1 wt% Sn-decorated MWCNTs. In addition, the bending reliability of Sn-58Bi solder increased approximately 25%.