Effects of CeO2 nanoparticles addition on shear properties of low-silver Sn–0.3Ag–0.7Cu-xCeO2 solder alloys

Abstract

In this article, the shear properties of Sn–0.3Ag–0.7Cu-xCeO2 composite solder alloys were investigated at strain rates of 10−3s−1, 10−2s−1, and 10−1s−1 under three different temperatures of 25 °C, 75 °C, and 125 °C. Scanning electron microscope equipped with Energy-dispersive X-ray spectroscopy was used to observe the microstructural evolution and the fracture surface of the composite solder alloys. The results show that appropriate addition of CeO2 nanoparticles can improve the shear stress of the composite solder alloys. However, the excessive addition of CeO2 nanoparticles could degrade the mechanical properties. With an increase in strain rate or a decrease in test temperature, the shear stress of all solder alloys shows an increasing trend. A modified constitutive model was used to describe the effect of strain rate and temperature on shear stress. The optimum addition concentration of CeO2 nanoparticles in Sn–0.3Ag–0.7Cu-xCeO2 solder alloys is about 0.5 wt%, which possesses the highest shear stress.