Copper Content in Solders
Copper is amongst those metals which are dissolved very quickly by liquid solder. In wave- and selective soldering systems, this leaching of the copper from the printed circuit board raises the concentration of copper in the baths. Especially lead-free tin based alloys tend to leach excessive amounts of copper very quickly from the tracks on the board. The rate of leaching is dependent on the alloy, the temperature and the dynamics of the solder wave.