Flux, or Solder Flux, is a kind of chemical used in automatic PCB assembly, hand soldering, or rework. It is basically used to clean surface of PCB before soldering process. These oxides deposited on the board may not permit good solder joints. If the solder joint is poor, there will be poor electrical conduction or poor flow of electricity through the circuit. Solder flux helps to de-oxidize metals (copper traces on the PCB and leads of electronic components) and helps better soldering and wetting. The activators in the flux promote wetting of the molten solder to the surface mount lands and component terminations or leads by removing oxides and other surface contaminants.
- Rosin Flux
- Water Soluble Flux
- No-Clean Flux