Zinc base solder wettability was poor, the appropriate flux could significantly improve its wettability. To join different content of the active material in the flux could also improve its corrosion resistance of substrate and wetting effects. This paper studies the effects of BTA corrosion inhibitor on Zn20Sn solder flux physical properties and the spreading performance, the results show that :when the inhibitor BTA content is less than 0.3%, the flux is not sticky.corrosive, no volatile matter content, stability all meet the national standard and spreading performance is good.

The development of energy saving technologies is very actual issue of present day. One of perspective directions in developing these technologies is the thermal energy storage in various industry branches. To meet the requirement of high temperature of solar heat transfer and thermal storage, this paper calculated several sets of data for lots of pure salts and salt mixtures. The results show that, comparing with the ternary carbonate salt (potassium carbonate (0.7) - sodium carbonate (0.1) -potassium chloride (or sodium chloride)), the ternary chloride salt (potassium chloride (0.037) - calcium chloride (0.5) - sodium chloride) is more perspective.

A new Bi5Sb8SnRE quaternary alloy was formed by adding 0.25wt%-0.75wt% rare earth (RE)Er into Bi5Sb8Sn solder alloy to study the effect of its mechanical property.The results show that adding micro amount of Er could refine the microstructure.Meanwhile,more uniform microstructure,improvements of the mechanical properties were obtained with Er additon.Comparing with Bi5Sb8Sn matrix, the tensile strength and shear strength increased by 41.8% and 83.0% respectively when Er adds up to 0.5wt.%; However,the Microstructure coarsened and the mechanical properties were decreased when the addition of Er more than 0.5wt.%.

In this paper a novel quaternary alloy is formed by adding a small amount of rare earth Er (RE) into Bi5Sb8Sn solder alloy to improve its technological properties. The influences of Er on the resistivity and spreading properties of the novel solder alloy were systematically investigated. Studied results show that adding 0.25~0.75wt.% RE into Bi5Sb8Sn solder alloy, the resistivity changes little,while the wettability demonstrated a significant improvement.The spreading area reaches 27.22mm2 and increases by 23% than the Bi5Sb8Sn matrix soler when the content of RE is 0.5wt.%.With increasing the content of Er ,the spreading area of solder alloy decreases, but it is still higher than that of the Bi5Sb8Sn solder alloy. It is mainly closely related to new phases with RE ,the form of compounds and thickness of interface intermetallic compounds in the Bi5Sb8SnRE solder alloy.