Title: Microstructure and mechanical properties of lead-free Sn-Cu-Ni composite solder paste reinforced with silicon (Si) particles
Abstract: This study investigates the effects of Si particles addition into a Sn-Cu-Ni lead-free solder paste on its microstructure and mechanical properties. The Sn-Cu-Ni-Si composite solder pastes were prepared by mechanically mixing Si particles into Sn-Cu-Ni solder paste. From microstructure observation, it was found that the area of β-Sn has decrease and the bulk microstructure has been refined. The result for shear test indicates that composite solder joint exhibited higher shear strength as compared to monolithic Sn-Cu-Ni solder joint. It is suggested that Si particles impart their positive influence on the microstructure formation hence improved the mechanical properties of composite solder paste.