Different Types of Flux

There are different types of soldering flux, like liquid flux, tacky flux, flux core, and flux in solder paste. Each type has its own benefits and works well for specific soldering jobs. The one you choose depends on things like the kind of soldering you're doing, how easy it is to reach the joint, the way you want to apply the flux, and the needs of your soldering project. 

There are 4 different kinds of flux, each of which has its own characteristics and serves different purposes:

Liquid Flux 

  • Liquid consistency
  • Typically contained in a bottle, syringe and even comes as a pen
  • Applied to solder joints/components before the solder is applied
  • Cleans the surface, improve solder flow, and enhance the quality of the solder joint.
  • Usually applied by spray, foam or selective applicator such as a brush or pen

Tacky Flux

  • Sticky/gel-like texture to adhere to surfaces when soldered, preventing it from dripping or running
  • Often used in situations where there is a need for the flux to stay in place during the soldering process, e.g soldering vertical or overhead joints

Flux Core

  • Solid wire with hollow core filled with flux
  • Melts during the soldering process, and release flux which helps clean the surfaces and facilitate the soldering process.
  • Convenient to use as it combines both the solder and flux into a single product, eliminating the need for separate flux application.

Flux in solder paste

  • Paste-like mixture
  • Mixture of solder alloy and flux
  • Used in surface mount technology (SMT)
  • Cleans the solder pads and components, makes sure the solder sticks well, and keeps everything in place before the soldering process.
  • Precise application of solder paste can be done with the aid of stencils
Back to blog