What are the pros/cons of halide vs. halide-free fluxes?
A. The only advantage that I can think of for halides is that it makes the flux more active, or more aggressive. If you have boards or components that are coming in an un-solderable condition, you need an aggressive flux to get decent wetting. It is our opinion that you need benign fluxes in assembly and if you are getting in parts that are un-solderable, necessitating an aggressive flux, your component supply has a problem with HIS process that needs to be addressed. The down side to halides are many. On any circuit assembly, there is what we refer to as “The Triad of Evil”. This would be an electrical potential, moisture, and an ionic contaminant. Halides contribute to the ionic contaminant part of the equation. The higher the amount, or the more electro-active the material, the greater the risk of electrochemical failures. Chloride is the most common contaminant from halide bearing fluxes. The only halide more electronegative in nature is fluoride. Imagine a classic Venn diagram (th
