Flux is a chemical compound that helps prepare the metal surfaces for soldering by removing oxides, promoting wetting, and enhancing the flow of solder. It typically comes in the form of a paste, liquid, or core within the solder wire.
When joining two metals in a soldering process, like used in PCB assembly, flux is required to achieve a true metallurgic bond. That ensures the solder joint doesn’t crack or come loose even with the day-to-day wear-and-tear. This article covers the types of fluxes available, the advantages and disadvantages of each, and options for flux removal.
Flux aids in soldering and desoldering processes by removing oxide films which form on the surface of metals being soldered. It increases the wetting ability of the solder, causing it to flow more uniformly over surfaces without balling-up (dewetting).
Flux plays a crucial role in electronic soldering, facilitating the process and ensuring reliable connections between components. Soldering involves joining metal surfaces using a molten alloy known as solder. However, during the soldering process, various impurities, oxides, and contaminants can hinder the formation of a strong bond. This is where flux comes into play.
Flux is a chemical compound that helps prepare the metal surfaces for soldering by removing oxides, promoting wetting, and enhancing the flow of solder. It typically comes in the form of a paste, liquid, or core within the solder wire. The flux compound contains active ingredients, such as rosin or organic acids, that react with the oxides on the metal surface.
When heated, the flux activates and starts to remove the oxides, preventing them from interfering with the soldering process. The flux also promotes wetting, which is the ability of the molten solder to spread and adhere to the metal surfaces. By reducing the surface tension of the solder, flux ensures that it flows smoothly and evenly, creating strong and reliable solder joints.
Additionally, flux helps prevent the re-formation of oxides during soldering by creating a protective barrier on the metal surfaces. This barrier shields the freshly cleaned metal from the surrounding atmosphere, preventing rapid oxidation and ensuring a clean and reliable solder joint.
