Lead‐free alloys

In recent years, efforts to develop alternatives to lead‐based solders have increased dramatically. These efforts began as a response to potential legislation and regulations restricting lead usage in the electronics industry. Lead is extremely toxic when inhaled or ingested. As researchers began to focus on Pb‐free solders, they recognized their value in high temperature applications (e.g. automotive manufacturing) where Sn/Pb solders do not meet the requirements. There are many factors to consider when developing lead‐free alloys: manufacturability, availability, reliability, cost and environmental safety. Of these, the most challenging and time consuming is the reliability of alternative solders. The lead‐free alloys available cannot be used as a drop‐in replacement for the SnPb or SnPbAg. The introduction of lead‐free solder alloys may mean having to use alternative component and PCB metallizations, PCB materials, solder fluxes, etc.