Molten flux parameters

Wettability is the capacity of the molten solder to react with the base metal at their mutual interface and establish a bond there. The wettability of liquid solders is largely an intrinsic property between the specific solder composition and the base metal composition. On the other hand, spontaneous spreading is impacted by several parameters base metal surface condition, wettability (solder/base metal interface reaction), and the flux. The synergistic roles of the molten solder, base metal, and flux on the combined properties of wetting and spreading, that is, the alloy s solderability, can be described by Young s equation ... 

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