The reflow soldering process is very prone to poor soldering conditions such as false soldering and false soldering. Virtual soldering and false soldering will seriously harm the performance of the product and greatly increase the maintenance cost of the product. Reflow soldering false soldering and false soldering are caused by many reasons, Guang Shengde here to share the preventive treatment of reflow soldering false soldering and false soldering.

1. Waterproof storage of electronic devices

If the electronic device is placed in the air for too long, it will cause the electronic device to absorb water, and the electronic device will oxidize in the air, which will cause the electronic device to be unable to fully eliminate the metal oxide in the whole process of electric welding, resulting in the shortcomings of false welding and false welding. . Therefore, in the whole process of electric welding, it is necessary to bake electronic devices with moisture and replace electronic devices with air oxidation. Generally, electric ovens are installed in PCBA manufacturing plants to bake electronic devices with water vapor.

2. Using famous brand solder paste

The shortcomings of false soldering and false soldering in the reflow soldering process are very closely related to the quality of the solder paste. The unscientific configuration of the alloying materials and the flux in the solder paste composition is very easy to cause the flux activity in the reflow soldering process is not strong, and the solder paste cannot sufficiently penetrate the solder layer, which will cause false soldering, Disadvantages of false welding. Therefore, it is possible to select solder pastes from famous brands such as Senju, Alpha, and Victory.

3. adjust the main parameters of solder paste printing

Most of the problems of false soldering and false soldering are due to the lack of tin. During the whole process of solder paste printing, the working pressure of the squeegee should be adjusted. A suitable screen should be used. The screen opening does not need to be small to prevent the amount of tin from being too small. situation.

4. adjust the temperature curve of the reflow oven

When carrying out the reflow soldering process, it is necessary to control the reflow soldering time. The time in the heating zone is not enough to make the flux active enough to eliminate the surface metal oxide at the reflow soldering area and the time in the reflow soldering area. Too long or too short will cause false welding and false welding.

5. Reflow soldering should be used as much as possible to reduce manual soldering

Generally, when using electric ferrochrome to carry out manual welding, the technical standards for welding staff are relatively high, the temperature of the soldering iron tip is too high or too low, or the electronic components of the welding are loosened during electric welding, which is very easy to cause false Soldering and false soldering, the application of reflow soldering can reduce the external elements of human factors and improve the quality of reflow soldering.

6. Prevent the temperature of electric ferrochrome from being too high or low

After PCBA reflow soldering, during production, processing and maintenance, electric ferrochrome is used for manual electric welding. In the application of electric ferrochrome, non-standard actual operation will cause the temperature of the soldering iron tip to be too high or too low, which is very easy to cause false welding and false welding. Therefore, when soldering with a soldering iron, the tip of the soldering iron should be kept clean and tidy. According to different components and the size of spot welding and the appearance of components, choose electric ferrochrome with different output power types, and control the soldering temperature of the soldering iron at 300℃—360 ℃ in the middle.