Table of Contents
Introduction to Solder Flux
Solder flux plays a vital role in the soldering process, serving as a water-based paste that enhances the bond between metals. It combines a cleaning agent, an activator, and a wetting agent to effectively remove oxides and contaminants from the surfaces to be soldered.
By ensuring a clean connection, flux allows melted solder to flow smoothly and adhere properly, resulting in stronger and more reliable joints. The activator is a specific chemical component designed to target and eliminate impurities, ensuring optimal soldering performance.
Components of Solder Flux
The main components of flux include:
- Cleaning Agent: Removes contaminants.
- Activator: Specific chemicals like ammonium chloride or hydrochloric acid that eliminate oxides and dirt.
- Wetting Agent: Helps solder adhere to the metal surface.
Types of Solder Flux
Commonly there are three types of fluxes for electronics applications: rosin, water-soluble, and no-clean fluxes. These fluxes are selected depending on the need and applications. Fluxes can be made from ammonium chloride, hydrochloric acid, zinc chloride, or rosin.
Water-soluble paste fluxes are applied by brush or dispensed from a syringe into the appropriate area, then heated using conventional methods. A no-clean flux does not require any cleaning after soldering. It is preferable to use the flux that matches the solder wire you are using.
Categories of Solder Wire
There are three main categories of solder wire: Lead-based, lead-free, and flux-core solder.
Flux-Core Solder: This type of solder wire has the flux embedded in the solder wire itself, eliminating the need for additional flux while soldering.
Lead-Based Solder: This type is a traditional solder wire with a 60/40 (tin/lead) mixture, the most common one available in the market. Its melting point is around 180-190 degrees Celsius. With higher tin concentration, it will have better tensile and shear strengths. You can also find non-corrosive solder wire having a 63% tin and 37% lead mixture with good solderability and insulation resistance.
Lead-Free Solder: Lead affects health and the environment, so lead-based solder wire is not the ideal solution. Lead-free solder usually contains 99.3% tin and 0.7% copper, with a higher melting temperature of around 217 degrees Celsius.
Recommended Solder Flux Brands
Solder flux from Noel and Glare India are found good enough for hobbyists. Bharti, Amico, TINNZTES, Globomotive, and Kester are some other popular solder wire brands. These brands are being mentioned based on our personal experience and reviews found online and are not necessarily the best ones.
Don’t miss our article Your Guide To Soldering, for comprehensive tips and techniques to enhance your soldering skills. Dive in to discover essential insights that will elevate your projects to the next level!
