Effect of Type of Reinforcement at Nanolength Scale on the Tensile Properties of Sn-0.7Cu Solder Alloy

In this study, Sn-0.7Cu solder alloy was reinforced with Al₂O₃ (50 nm) and ZrO₂ (45 nm) nano particulates to form Sn-0.7Cu/Al₂O₃ and Sn-0.7Cu/ZrO₂ composites. The volume percentge of the Al₂O₃ and ZrO₂ nanoparticulate reinforcement was kept at 1.5%. The composites were synthesized using powder metallurgy technique assisted with microwave sintering and incorporating hot extrusion as secondary processing technique. The extruded materials were characterized in terms of microstructural, physical and mechanical properties. The density values of composite solder materials were found to be lower when compared to monolithic alloy. Microstructure characterization revealed bigger pores in Sn-0.7Cu/ZrO₂ composite samples compared to Sn-0.7Cu/Al₂O₃ composite samples. The results of room temperature tensile testing revealed that 0.2% yield strength and ultimate tensile strength of composite solder materials increased when compared to monolithic solder. Among the composite solders, the 0.2% yield strength and ultimate tensile strength of Sn-0.7Cu/Al₂O₃ composite was found to be distinctly superior to Sn-0.7Cu/ZrO₂ composite.