15. Thermal Capability of Components

For surface mount components, the most used alloy family for reflow soldering, the SnAgCu, shows a liquidus temperature ranging between 217 and 221°C, and it is agreed that during reflow the coldest solder joint temperature should be no less than 230°C. Accordingly, the components are submitted to temperatures notably higher than those to which they were submitted with the Pb technology and much of them had to be re-qualified. What can one say today in connection with the thermal compatibility of components with the lead-free soldering processes? To answer this question, we examined more than 125 web sites of components makers and we also learned from the members of the Components Technical Experts Group. The obtained results are exposed below by distinguishing active and passive components.