The Effects of Ni Nanoparticles Addition on Shear Behavior and Microstructure of Sn-Ag Lead-free Solder

摘要

In this article, the effects of Ni nanoparticles addition on shear property and microstructure of Sn-3.5Ag Lead-free solder joint was studied. The nickel nano-composite Sn-3.5Ag solder was prepared by adding dispersant to the dry nanoparticles and mechanically stirred Ni nanoparticles into the Sn-3.5Ag Lead-free solder paste. The shear force of the Sn-3.5Ag solder, 0.5 and 1.0 wt% nickel nano-composite solder was tested respectively at reflow 120s and 240s. The result shows that adding nickel nanoparticles can improve the shear performance of the soldered joint; the shear force of the soldered joint is highest when adding 0.5wt% Ni nanoparticles at reflow 240s. The SEM observations shows that the hexagonal Cu6Sn5 IMC (intermetallic compound ) in the inside solder is disappears gradually and the morphsa of the IMC that on the interface of the solder joint becomes planar after adding Ni nanoparticles into solder.