Flux and cleaning materials
Flux removes oxides from the metal surfaces and keeps them clean while the solder wets the joint. The right flux depends on your alloy, your process and whether the board is cleaned afterwards.
We supply a complete range of flux and cleaning materials through our flux partner, including custom flux for special applications, and can help you choose between the types below.
Five types of flux
- No-clean flux
- Leaves little residue, and what remains is safe to leave on the board, so there is no wash step.
- Water-based flux
- Active flux whose residue is removed with water after soldering.
- Rosin-based flux
- The traditional flux, made from natural or modified rosin, reliable on a wide range of metals.
- Halide-free flux
- Contains no halides, for assemblies where residues must not cause corrosion.
- VOC-free flux
- Water-carried with no volatile organic compounds, for lower emissions and safer handling.
Applying and maintaining flux
- Match the flux to the alloy and process. Lead-free alloys run hotter, so choose a flux rated for the higher temperature.
- Apply an even, thin layer by spray, foam or brush. Too much flux leaves residue; too little leaves bridges and poor wetting.
- On wave lines, check the flux density or solids content every shift and top up with thinner as it evaporates.
- Preheat the board enough to drive off the carrier before it meets the solder, which reduces spattering and voids.
- Clean water-based and rosin residues when the product requires it, using the cleaner recommended for that flux.
- Store flux sealed, away from heat and sunlight, and use it within its shelf life.
Flux partner: Shree Swaminarayan Industries.
Used with
- Wave soldering
- Selective soldering
- Hand soldering and rework
- Tinning