The flux that is rather short-lived in smt patch processing
Flux is indispensable in smt patch processing. A suitable flux can not only remove oxides and prevent re-oxidation of the metal surface, but also improve solderability and promote energy transfer to the soldering area. Choosing high-quality flux is the secret of Jingbang Technology’s brand building. The following Dongguan SMT chip processing factory will introduce you to four common fluxes.
SMT chip processing
1. Rosin type flux;
Rosin type flux is the most common flux. Its soldering performance is weak and corrosive, and the residue is basically non-corrosive, leaving a protective film on the substrate, but it is sometimes sticky and hygroscopic, and it is generally not cleaned.
2. Water-soluble flux;
Water-soluble flux, as the name implies, has high solubility in water, strong activity, and good flux performance. The residues after welding can be cleaned with water. The water-soluble flux has strong deoxidation ability, strong flux performance, stable storage and non-toxicity. The residue after welding is easily soluble in water and does not pollute the environment. After cleaning, the pcb meets the cleanliness requirements, is non-corrosive, and does not reduce the electrical insulation performance.
3. No-clean flux;
No-clean flux refers to a flux that contains only a small amount of harmless flux residue after soldering and does not need to be cleaned after soldering. It is not only non-toxic, tasteless and less smoke, but also does not pollute the environment and has good solderability. Since there are very few residues after welding, the pcb panel is dry and non-sticky, and it can also be tested online. Moreover, the storage period of no-clean flux can be as long as one year.
4. No VOC flux;
VOC is a substance harmful to the environment. In recent years, due to the increasing awareness of environmental protection, VOC-free fluxes have been developed. It is prepared by using deionized water instead of alcohol as a solvent, adding active agents, foaming agents, wetting agents, non-VOC solvents, etc., in a certain proportion. However, there is a new requirement for VOC-free flux. Before wave soldering, if the water is not completely volatilized, solder splash (commonly known as fried tin), pores and voids will be formed.
