Reasons for component misalignment after reflow soldering

The phenomenon of component misalignment or misalignment after reflow soldering may be caused by poor wetting of the solder or comprehensive factors such as equipment. Observing the occurrence time of defects can be divided into two situations for analysis and resolution.

1、 Component misalignment before reflow soldering

Firstly, observe whether the position of the assembled components on the substrate is offset before welding. If this is the case, check whether the bonding force of the solder paste meets the requirements. If it is not due to the solder paste, check the installation accuracy and position of the mounting machine again to see if there is any deviation. The installation accuracy of the mounting machine is insufficient, or the position is offset, or the bonding force of the solder paste is insufficient, which may cause component displacement.

2、 Component misalignment during reflow soldering

Although the wettability of the solder is good and has sufficient self adjustment effect, component displacement ultimately occurs. At this time, it is necessary to consider whether there is vibration or other effects on the conveyor belt inside the reflow soldering furnace and inspect the reflow soldering furnace. If it is not for this reason, the Manhattan defect factor of the component can be considered, whether it is due to the rapid melting of the solder on one side of the welding area on both sides, and the deviation of the component caused by the surface tension during melting.