Generally, why do we use flux in solder wire? Rosin is generally used for welding small parts, and flux is used for welding large parts. Everyone knows that rosin is used for circuit boards, and flux is used for single-piece welding. Want to know how to use flux? Everyone should first understand what flux is?

Everyone should know that because the surface of the copper foil on the CCL will oxidize, the solder will also oxidize at high temperature. If the oxide layer is not removed with flux, there will be a virtual soldering phenomenon, and a reliable ohmic connection cannot be guaranteed.

Solder wire uses rosin (resin) flux as the main flux. Earlier, some manufacturers introduced "water-washed solder wire". At present, some solder wire manufacturers have also introduced "no-clean solder wire".

When using it, there are several problems with solder wire that are often reflected, such as: slow tinning speed, dull solder joints, corrosion of soldering iron tips, too much smoke, too irritating smell, etc.; among these problems, "slow tinning speed" It may be caused by insufficient power of the soldering iron, low tin content, etc., but in the case of a certain tin content, the activation performance of the flux in the tin wire and the surface wetting performance are also the main reasons for determining the tinning speed; "Brightness" is directly related to the tin content, but in the case of a certain tin content, a strong active flux may cause the solder joints to be dull; the important reason for "corroding the soldering iron tip" is that there is too much arsenic in the tin alloy , but when the activity of the flux is strong, or adding an inorganic activator, it may also cause corrosion of the tip of the soldering iron; as for "too much smoke" and "too irritating smell" are subjective adverse conditions, but the flux in the flux Improper selection of activators, surfactants or additives is the main cause of this situation.