Soldering terminology

In soldering, flux and solder always form an inseparable unit. Solder paste is obtained from powdery solder which is mixed with a fluxing agent and cored solder contains a flux core. Flux consists of the following components:

1. Activator : Substance used for releasing the metal to be soldered from oxides and for preventing oxidation during soldering. T he flux must be melted and poured over the solder.

2. Binder : If WW rosin is used as a binder, it also performs the tasks of an activator in the same time. Generally, a binder is used; a) as a carrier for heat and reaction products; b) to reduce the surface tension of the solder in order to promote its dispersion; c) to protect the metal against re-oxidation at soldering temperature.

3. Solvent : Used mainly as a diluent for flux.

4. Solubilizer : Substance used for preventing the solidification of the binder before cleaning and enhances the cleaning effect. Also, it promotes foam building in foam fluxers in wave soldering and it is used as a cosolvent.

   when the flux does not dissolve in the solvent. For this latter purpose, esters, ethers and ether alkanols are commonly used.