Microstructure, mechanical properties, and drop reliability of CeO2 reinforced Sn–9Zn composite for low temperature soldering

In this study, CeO2 reinforced eutectic Sn–9Zn–xCeO2 composite specimens were prepared by mixing and melting route. The CeO2 nanoparticles were synthesized by chemical precipitation method. The composite samples were produced by adding CeO2 nanoparticles from, x = 0, 0.3, 0.6 to 0.9 wt% in the eutectic Sn–9Zn matrix. The microstructural analysis revealed that the presence of CeO2 in Sn–9Zn–xCeO2 matrix refined the Zn needles when CeO2 was added up to x = 0.6. The wetting properties of these solders were considerably enhanced (≈17%) over monolithic Sn–9Zn alloy. The melting properties of Sn–9Zn–xCeO2 solders showed a narrow pasty range 3.9 °C–7.6 °C. The mechanical strength and ductility of the solders were also improved after addition of CeO2 nanoparticles in the matrix up to x = 0.6. An optimum fraction of 0.6 wt% CeO2 in eutectic Sn–9Zn alloy is recommended to obtain a set of enhanced wetting, strength and drop reliability of Sn–9Zn solder.