In the PCBA processing process, some PCBA boards that require double-sided mounting require two reflow soldering. If there are plug-in components, wave soldering is required, then the PCBA needs to perform 3 times of soldering.
So what is the impact of PCBA multiple times reflow?
1. The impact on the PCB
PCBA has been baked at high temperature for many times, which is easy to cause bow and twist of the PCB, especially some relatively thin and relatively large PCBs. At this time, the fixture can be used to prevent bow and twist. In addition, the multiple times high-temperature baking of the OSP process PCB will cause the oxidation of the pad of the PCB to be severe, resulting in poor soldering.
2. The impact on the components
PCBA is reflowing many times, and the most direct impact is easy to damage components. Because the temperature of lead-free soldering is relatively high, the soldering temperature is above 250 °C, which is relatively harmful to components, and it is also likely to cause component failure.
In the PCBA process, should reduce the times of the reflow as much as possible. If it is necessary to pass the reflow multiple times, the means such as the fixture can be increased to reduce the damage to the PCBA.
