HASL is the predominant surface finish used in the industry. The process consists of immersing circuit boards in a molten pot of a tin/lead alloy and then removing the excess solder by using 'air knives', which blow hot air across the surface of the board.
to temperatures up to 265°C which will identify any potential C that works best for you and your process while still keeping the environment safe is has become a much more practical solution.
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