Q2: What should we pay special attention to when changing process from Lead based solder to Leadfree solder?
A2: Many things have to be considered on beforehand but the most important is to:
- assure that the PCB and components can withstand the higher temperature impact during reflow soldering
- be aware that even though std 63Sn-37Pb can cause electromigration then the leadfree Sn 4.0Ag -0.5Cu significantly increase the probability and speed for migration so protection against liquid ingress must be thoroughly considered.
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