In lead-free soldering there are many solder alloys that can be used, most of these alloys are often only developed for a specific process e.g. like for reflow soldering.
Apart from that there are often different component-lead coatings which have to be used in the assembly. Finally the coating on the PCB will have its effect on the joint formation.
Next some aspects related to this 'mix' of combinations will be elucidated.
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