Solder Flux

What is a Solder Flux?

Solder flux is a specialized chemical cleaning agent designed to enhance the soldering process by removing oxidation and other contaminants from metal surfaces. This cleaning action is crucial for ensuring a strong and reliable bond between the solder and the metal components. Solder pastes contain solder alloy particles combined with flux where solder flux functions to break down the oxidation barrier that could weaken the solder joint. Without flux, the risk of creating weak or unreliable solder joints increases significantly, making it an essential component in soldering applications. 

Solder flux and solder paste are often mistaken as the same thing, but they serve distinct purposes. Solder flux acts as a general-purpose agent that aids in tasks like oxide removal and metal surface tension reduction and is available in solid, liquid, and gaseous forms. In contrast, solder paste combines solder powder, flux, surfactants, etc., and is primarily used to attach components electrically to PCBs. There are three main types of flux: inorganic acid flux, organic acid flux (or water-soluble flux), and rosin flux, each with unique properties and applications. The flux r is carefully selected based on PCB type and soldering method. Proper application of solder flux is essential for robust connections and requires a thorough cleaning of surfaces and diligent removal of residual flux post-soldering to achieve ideal PCB performance. 

Key parameters of solder flux 

• Type of Flux: Fluxes can be solid, liquid, or gaseous. They can also be organic-based (water-soluble) or inorganic. 
• Classification: Fluxes are rated as RO (rosin), OR (organic), IN (inorganic), and RE (resin/synthetic resin). The activity of the flux solution is rated as L (low activity or <0.5% halide), M (medium activity or 0 to 2% halide), and H (high activity or 0 to >2 % halide). Fluxes are classified for halide (Cl- or Br-) content as 0 (no halides) or 1 (some halides). Some examples of flux classification are – ORH1, ROH1, ORL0, ROL1 etc. 
• Package Type: The form of packaging the flux is available in, like a syringe, cartridge, or jar. 
• Shelf Life: The duration of the lifespan of the flux before expiring and being susceptible to defects and failures. 

PCB Directory has listed Solder Fluxes from the leading manufacturers in the industry and made it easy for users to find them based on their requirements. You can specify the type of flux, classification, and other parameters to find a Solder flux that meets your requirements. You can view flux specifications, download the spec sheet, and get a quote. Quotes requested are routed to the manufacturers.

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