What occasions are they used? What do we usually use when welding with iron iron?
Solder paste: used for patch welding of circuit boards. Solder paste is a paste of a mixture of tin, silver, alloy particles and soldering flux.Soldering flux: a kind of auxiliary welding material. The main component is rosin. A surface oxide used to clean the metal of a welded part.These two substances are nothing at all!
The main composition of flux and its function:A. activator (Activation): the composition is mainly used to remove the PCB copper film pad surface and parts of the welding parts of the role of oxidation substances, but also has to reduce tin, lead surface tension effect;B. thixotropic agent (Thixotropic): this component is mainly to regulate the viscosity of solder paste and printing performance, play a role in printing to prevent trailing, adhesion and other phenomena;C. resin (Resins): this component is mainly used to increase the adhesion of solder paste, and to protect and prevent the re oxidation of PCB after welding. This component plays an important role in the fixation of parts;D. solvent (Solvent): this component is the solvent of the flux composition. It plays a uniform role in the mixing process of solder paste, and has a certain influence on the life of solder paste;
Solder PCB board will use solder paste. On other occasions, usually not
