With the increasing fragmentation of electronic circuits and connections in the new electronics industry and the need for greater strength of these connections, conventional soldering technologies no longer guarantee the proper performance of electronic components. On the other hand, due to the environmental hazards associated with lead-containing solders in the electronics industry, many laws have been enacted to remove lead and lead-containing solders, and many efforts have been made around the world. Therefore, in order to develop lead-free solder with low melting temperature and suitable mechanical, physical and thermal properties, many studies have been done. Sn-9Zn utectic alloy is one of these alloys that has a low price and its melting temperature is close to Sn-37Pb eutectic alloy. Is. However, the low oxidation resistance and poor wettability of this alloy have limited its use. Previous research has shown that these problems can be reduced by nanocomposing these solders, which improves their performance. In this research, for the first time, the plastic deformation method is used to make Sn-9Zn nanocomposite solder reinforced with silica nanoparticles. The ultimate goal of making this nanocomposite lead-free solder is to create a solder with a relatively low melting point, good adhesion to the substrate, and a fine-grained, stable structure with a uniform distribution of reinforcing particles in the field that can ultimately meet economic expectations. Eliminate consumer industries. In this regard, in addition to choosing the type and method of making lead-free nanocomposite solder, which has economic justification; The costs associated with producing reinforcing nanoparticles are also significant. Another innovation of this research is related to the synthesis of these nanoparticles from lead-acid battery waste. First, Sn-9Zn alloy was prepared by melting and vacuum method. Microstructural studies, X-ray energy diffraction spectroscopy tests, differential spectroscopy, and X-ray diffraction tests were performed to evaluate the alloy properties. Then, SiO2 nanoparticles prepared and characterized by pyrolysis were added to the alloy by extrusion method in angular non-sectional channels with weight percentages of 0.25, 0.5, 1 and 1.5. The results of mechanical and physical properties tests and microstructural studies showed that the composite sample with 0.5% by weight nanosilica is the optimal sample. This sample compared to the alloy sample increased by 70, 37, 16% in shear strength, respectively. It has tensile strength and microhardness. The presence of nanoparticles improves the wetting angle due to the barrier against the growth and penetration of intermetallic compounds.
