Papers by Author: G.X. Wang

Abstract: Ag and SnO2 nanopowders were synthesized by reverse-micelle method. The reverse micelles were prepared to form tiny aqueous droplets dispersed in oil-based solvents. Two reverse micelles containing metallic salts and reductive agents were rigorously mixed to form nanoparticles inside aqueous droplets by a reductive reaction. The spherical powders of 20~50 nm were formed during the process. The resulting Ag and SnO2 nanopowders were examined as the anode electrode for lithium-ion cells. The reversible discharge capacity of the Ag and SnO2 nanopowders after 25 cycles were 315 and 380 mAh/g, respectively.

Abstract: A series of experiments conducted on a lead-free eutectic solder (Sn-3.5%Ag) have shown that addition of trace amounts of nanometer-sized particles does have an influence on mechanical properties of materials. In this study, three different types of nanoparticles (copper, nickel and iron) were chosen as the reinforcing candidate. For each particulate reinforcement the reflow process was performed under identical cooling conditions. Addition of trace amounts of nano-particles alters the kinetics governing solidification of the composite solder paste while concurrently exerting an influence on microstructural development, particularly the formation and presence of second phases in the solidified end product. The nano-sized powder particle-reinforced composite solder revealed an increase in microhardness compared to the unreinforced monolithic counterpart.