Effects of Ni Additions on the Growth of Cu_(3)Sn in High-Lead Solders

摘要

In reactions between solders and Cu, additions of minor alloying elements, such as Fe, Co or Ni, to solders often reduce the Cu_(3)Sn growth rate. Nevertheless, the mechanism for this effect remains unresolved. To provide more experimental observations that are essential for uncovering this mechanism, growth of Cu_(3)Sn in the reaction between Cu and high-lead solders with or without Ni additions has been studied. The solders used for this study were 10Sn-90Pb and 5Sn-95Pb doped with 0 wt.percent, 0.03 wt.percent, 0.06 wt.percent, 0.1 wt.percent or 0.2 wt.percent Ni. Reaction conditions included one reflow at 350 deg C for 2 min and solid-state aging at 160 deg C for up to 2000 h. The effect of Ni on the growth of Cu_(3)Sn is discussed in detail based on the experimental results.