Preparation, hardness studies and characterization of 88 Sn-7.5Zn-2.5Al-2In and 88 Sn-7 Zn-2Al-2.5 In lead free soldering alloys

Soldering uses lead as one of its alloying elements because of the low melting point of lead. Recent research has focused on lead free solders as lead is seen as a poisonous elements. In this work, two lead free alloys, namely 88 Sn-7.5Zn-2.5Al-2 In and 88 Sn-7Zn-2 Al-2.5 In were prepared using induction melting method in an argon atmosphere. Melting points of the alloys were 203.7Cellcius and 201.6 Celsius as determined by Differential Scanning Colorimetry (DSC). Vickers hardness tests were conducted. Hardness values were found to be higher than normal lead based soldering alloys. The lead free solders were characterized using Energy Dispersive X-Ray Spectra (EDS). Microstructural studies were also done to study changes in microstructure with Indium. (paper)