Why does PCBA have bubbles during soldering?
The pores produced by the welding of PCBA boards are also known as bubbles. Generally, reflow soldering and wave soldering during PCBA processing will produce pores, so how to improve the problem of PCBA board soldering pores? PCBA manufacturer FASTPCBA will explain it in detail for you.
1. Bake Bake PCBs and components that have been exposed to the air for a long time to prevent moisture.
2. Control of solder paste The solder paste contains moisture and is prone to pores and tin beads. First select a good quality solder paste. The temperature recovery and stirring of the solder paste are strictly performed according to the operation. The time that the solder paste is exposed to the air is as short as possible. After the solder paste is printed, reflow soldering needs to be carried out in time.
3. Workshop humidity control Monitor the humidity in the workshop in a planned way, and control it between 40-60%.
4. Set a reasonable furnace temperature curve Test the furnace temperature twice a day, optimize the furnace temperature curve, and the heating rate should not be too fast.
5. Flux spraying During wave soldering, the spraying amount of flux should not be too much, and the spraying should be reasonable.
6. Optimize furnace temperature curve The temperature of the preheating zone needs to meet the requirements, not too low, so that the flux can be fully volatilized, and the speed of passing the furnace cannot be too fast.
There may be many factors that affect PCBA soldering bubbles, which can be analyzed from the aspects of PCB design, PCB humidity, furnace temperature, flux (spray size), chain speed, tin wave height, solder composition, etc. It needs to be debugged many times. It is possible to get a better process.