Study on the properties of Sn-9Zn-xCr lead-free solder

The influences of different Cr content to lead (Sn)-Zn solder were investigated. Sn-9Zn-xCr shows finer and more uniform microstructure than Sn-9Zn. Thermal gravimetric analysis (TGA) and Auger electron spectroscopy (AES) results show that adding Cr significantly improves the oxidation resistance of Sn-9Zn solder, and reduces the thickness of oxidation film of Sn-9Zn-xCr solder. When Cr content is 0.1%, the Sn-9Zn-0.1Cr solder have the best oxidation resistance. In addition, the effect of Cr addition on the wettability, melting point and mechanical properties of Sn-9Zn solder was discussed. (C) 2007 Elsevier B.V. All rights reserved.