Subsidiaries of CXOnline network : ICNET | | CXO.lab



How to weld electronic components quickly? Electronic circuit welding components

Date:2022-08-03 18:05:44 Views:114

At present, soldering technology is mainly used in the welding of electronic components. Tin welding uses tin alloy materials dominated by tin as solder. The solid solder wire is heated and melted by the heated electric iron, and then flows into the metal to be welded with the help of flux. Because the metal weldment and tin atoms attract, diffuse and combine with each other to form a wetted bonding layer, a firm and reliable welding point can be formed after cooling. In order to help you understand in depth, the following contents are sorted out by Chuangxin testing network for your reference.

1、 Pre welding treatment

Before welding, the welding parts of component terminals or circuit boards should be welded, generally including "scraping", "plating" and "testing".

"Scraping" is to clean the welding part before welding, and the general tools are knife and fine sandpaper. Generally, the terminals of integrated circuits are not cleaned before welding, but the terminals should be clean. For self-made printed circuit boards, first polish the surface of copper foil with fine sandpaper, clean the dirt on the printed circuit board, and then apply rosin alcohol solution or flux before use. For gold and silver plated alloy leads, the coating cannot be scraped off, and the dirt on the surface can be wiped off with an eraser.

"Plating" refers to tin plating on the scraped parts of components. The specific method is to dip rosin alcohol solution into the scraped parts of components, press the hot soldering iron head with tin on the components, and rotate the components to evenly coat a thin tin layer. If the wires of multi strand wires are polished, they should be screwed together first, and then tinned.

After scraping, the lead of components should be immediately coated with a small amount of flux, and then a thin tin layer should be plated on the lead with an electric soldering iron to avoid re oxidation of its surface, so as to improve the solderability of components.

"Test" is to use a multimeter to test whether the quality of all tinned components is reliable after "plating". If there are components with unreliable quality or damaged components, they should be replaced with components of the same specification.

2、 Operation steps

After pre welding treatment, welding can be formally carried out. Pay attention to different welding objects when welding, and the working temperature of the electric iron required is also different. When judging the temperature of the iron head, you can touch the electric iron with rosin. If there is a "squeak" sound when touching, the temperature is appropriate; If there is no sound, it can only make the rosin melt reluctantly, indicating that the temperature is low; If the soldering iron head smokes a lot when it touches rosin, it indicates that the temperature is too high.

Generally speaking, the welding steps mainly include the following three steps.

a. First melt a small amount of solder and rosin on the soldering iron head, and align the soldering iron head and solder wire at the same time.

b. When the flux on the iron head is not volatilized, contact the iron head and the solder wire at the same time to melt the solder.

c. When the solder soaks the whole solder joint, remove the soldering iron head and solder wire at the same time.

The time of welding process is generally 2 ~ 3S. When welding integrated circuits, the amount of solder and flux should be strictly controlled. In order to avoid damage to the integrated circuit due to poor insulation of the electric iron or the induced voltage of the internal heater to the shell, the method of unplugging the power plug of the electric iron and welding while it is hot is often used in practical applications.

③ Faulty welding and welding quality. During welding, ensure that each welding point is firmly welded and in good contact. Qualified solder joints are as shown in Figure 1 (a) and figure 1 (d). Their tin spots are bright, smooth and free of burrs, with moderate tin content, and the tin and the weldment are firmly fused, without false soldering and false soldering.


False soldering is a false soldering, which means that there is only a small amount of tin at the solder joint. It seems to be soldered on the surface, but it is not soldered in fact, resulting in poor contact. Sometimes, the lead can be pulled out of the solder joint by pulling it out by hand. The faults caused by this kind of faulty solder joint are sometimes absent and difficult to find.

The above is the content related to the welding of electronic components compiled by the core detection team. I hope it will be helpful to you. Shenzhen Chuangxin Online Testing Technology Co., Ltd. is a well-known professional testing institution for electronic components in China, with 3 standardized laboratories covering an area of more than 1000 square meters. The scope of testing services covers: electronic component testing and verification, IC authenticity identification, product design and material selection, failure analysis, function testing, factory incoming material inspection, component X-ray testing, taping and other test items.