Effect of Small Additions of Alloying Elements on the Properties of Sn-Zn Eutectic Alloy

摘要

Sn-Zn alloys have been considered for use as lead-free solders.Their poor wetting and oxidation resistance properties are the main obstacles that pre-vent them from becoming commercially viable solders.The effects of alloying elements,such as lanthanum,titanium,aluminum,and chromium,on oxida-tion resistance,wetting properties,and tensile properties of eutectic Sn-Zn solder are described herein.Results show the addition of alloying Ti,Al,and Cr can improve the oxidation resistance of Sn-9Zn solder.La,Ti,and Cr do not have much effect on the wetting properties,whereas Al worsens the wetting.Differential scanning calorimetry investigations reveal the solidus tempera-ture of these solders to be approx 200 deg C.Addition of Cr improves ductility while maintaining tensile strength.