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Electronic components are soldered on to a Printed Circuit Board (PCB) to form an electronic assembly. Earlier all solders contained Lead (Pb), but environmental concerns with Pb have paved the way for development of lead-free solders to replace the commercial Tin-Lead (Sn-Pb) solders in electronic packaging systems. Majority of lead-free solders available exhibit poorer properties and higher surface tension than traditional Sn-Pb alloys. Therefore lead-free solders require processing at higher temperatures. In mixed assembly technology, both Surface Mount Technology (SMT) and Through Hole Technology (THT) components are placed on the PCB. During production, SMT components are soldered initially followed by Selective Soldering process to solder the THT components. The need for higher processing temperatures result in higher thermal load on the board, resulting in complications of unwarranted …