What is the basis for using rosin in electric soldering iron
In the past few days, I often see people asking why rosin should be added to solder. Here I roughly summarize it. Rosin is the most commonly used flux, neutral. If it is a newly printed circuit board, apply a layer of rosin perfume on the surface of the copper foil before soldering. If it is a circuit board that has already been made, it can be directly soldered. In fact, the use of rosin depends on personal habits. Some people will dip the tip of the soldering iron in rosin after soldering a component. The use of rosin is also very simple, just open the rosin box and dip the tip of the energized soldering iron on it. If solid core solder is used for welding, it is necessary to add some rosin; if rosin solder wire is used, rosin can be omitted.
The role of rosin in soldering. Rosin will have weak acidity at the temperature of the electric soldering iron, which can clean the oxide layer on the soldering surface, so that the solder can infiltrate the soldering surface. Nowadays, there will be rosin in the middle of the solder used in the general electronics industry. Just dip some on the electric soldering iron, and the solder wire will go directly to the electric soldering iron to work. The types of flux can be roughly divided into three series: organic, inorganic and resin. Resin flux is usually extracted from the secretions of trees, which is a natural product and is not corrosive. Rosin is the representative of this type of flux, so it is also called rosin flux. Because flux is usually used in conjunction with solder, it can be divided into soft solder and hard solder corresponding to solder. Soft fluxes such as rosin, rosin mixed flux, solder paste and hydrochloric acid are commonly used in the assembly and maintenance of electronic products. In addition, they should be selected according to different welding workpieces in different occasions. When using flux, it must be applied in an appropriate amount according to the area size and surface state of the workpiece to be welded. If the amount is too small, the welding quality will be affected. If the amount is too much, the flux residue will corrode the components or deteriorate the insulation performance of the circuit board.
