Nanocomposite SAC solders: morphology, electrical and mechanical properties of Sn–3.8Ag–0.7Cu solders by adding Co nanoparticles

The effect of nanosized Co admixtures on the microstructure and physical properties of Sn–3.8Ag–0.7Cu solder and corresponding solder joints was investigated. The composite Sn–3.8Ag–0.7Cu ribbons with minor additions of Co nanoparticles (up to 1.0 wt%) were fabricated using the conventional planar flow casting method. The structure of nanostructured alloys was studied by X-ray diffraction and transmission electron microscopy. The electrical resistivity of Sn–3.8Ag–0.7Cu ribbons doped with nanoCo was measured by the standard four-point method. The microstructure and mechanical properties of corresponding solder joints (with Cu as substrate) were studied. It was shown that nanoCo additions led to minor changes in the electrical resistivity of Sn–3.8Ag–0.7Cu solder ribbons, while the nanoCo doped Sn–3.8Ag–0.7Cu solder joints (up to 0.5 wt% Co) revealed the reinforced microstructure accompanied by enhanced mechanical properties.© The Author(s) 201