Liquid-solid interfacial reaction between Sn3.8Ag0.7Cu solder and electrodeposited Fe-Ni alloys

Liquid-solid interfacial reaction of eutectic Sn3.8Ag0.7Cu solder on electrodeposited Fe-Ni layers with different Fe contents was investigated in a vacuum furnace with H2 protection. The results show low-Fe Fe-83 Ni layers are consumed faster by the liquid Sn3.8Ag0.7Cu, however, high-Fe Fe-53 Ni layers have a lower consumption rate with dense FeSn2 compounds formed at the interface. The consumption rate of Fe-74 Ni layer is between Fe-53 Ni and Fe-83 Ni. When Sn3.8Ag0.7Cu solder is reflowed on electrodeposited Fe-Ni layers, the formation of denser FeSn2 compounds at the interface can inhibit further interfacial reactions.