PCBA welding processing mainly refers to the production process of soldering PCB circuit boards and components through soldering process. Welding defects such as false welding are prone to occur during the welding process. Welding will seriously affect the reliability of the product and greatly increase the maintenance cost of the product.

The problem of virtual soldering defects in PCBA soldering processing is caused by many reasons, mainly because the solder can not fully wet the pads and component pins, and the components and circuit board pads cannot be fully soldered. In the production process, specific prevention can be done in the following ways.

1. Moisture-proof storage of components
If the components are placed in the air for too long, it will cause the components to absorb moisture and oxidize the components. As a result, the components cannot be fully removed from the oxide during the welding process, resulting in the defect of virtual welding. Therefore, in the welding process, the components with moisture should be baked, and the oxidized components should be replaced. Generally, PCBA processing plants will be equipped with ovens to bake components with moisture.

2. Choose solder paste from well-known brands
The virtual soldering defects that appear in the PCBA soldering process have a great relationship with the quality of the solder paste. The unreasonable configuration of the alloying component and the flux in the solder paste composition can easily lead to the weak flux activation ability during the soldering process, and the solder paste cannot fully infiltrate the pad, resulting in false soldering defects. Therefore, you can choose solder paste from well-known brands such as Senju, Alpha, and Victory.

3. Adjust printing parameters
The problem of virtual soldering is largely due to the lack of tin. During the printing process, the pressure of the squeegee should be adjusted, and the appropriate stencil should be selected. The stencil opening should not be too small to avoid too little tin.

4. Adjust the reflow soldering temperature curve
When performing the reflow soldering process, it is necessary to control the soldering time. The time in the preheating zone is not enough to fully activate the flux and remove the surface oxides of the soldering area. If the time in the soldering zone is too long or too short, it will cause false weld.

5. Try to use reflow soldering and reduce manual soldering
Generally, when using an electric soldering iron for manual soldering, the technical requirements for the soldering personnel are relatively high. The temperature of the soldering iron tip is too high or too low, or the soldered components become loose during soldering, which can easily cause false soldering. Using reflow soldering can reduce Human-made external factors improve the quality of welding.

6. Avoid too high or low temperature of the soldering iron
In the post-welding processing and maintenance of PCBA welding, manual welding is required with an electric soldering iron. When using an electric soldering iron, improper operation causes the temperature of the soldering iron tip to be too high or too low, which can easily cause false soldering. Therefore, when soldering, keep the soldering iron tip clean, choose different power types according to the size of different parts and solder joints, and device shape, and control the soldering temperature between 300℃-360℃.

The virtual welding caused during the PCBA welding process is caused by many factors. The above are just some of the more common reasons listed by FASTPCBA. Through these preventive measures, combined with the actual situation, the defects of virtual welding can be effectively reduced.