← Glossary

Flux Activation Temperature

The thermal level at which the chemical components of the flux become active and dissolve metal oxides on the base material surface. This creates a clean metallic contact area for the filler metal.

The activation temperature is the point where the flux really starts to work and etch away the oxide layer on the metal. If you're below it, nothing happens – the surface stays dirty and you won't get proper wetting. If you push it too far, the flux burns and leaves residues that can embrittle the joint or cause porosity. So you have to heat the part so that the flux can react cleanly, but not char. You can tell the right setting when the solder flows cleanly and spreads smoothly. If it beads or crumbles, the temperature or time wasn't right.

MetallurgieSchweißtechnik

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