Factors Affecting The Quality Of PCBA
If one word is used to describe the manufacturing and processing of PCBA, it is complicated. Because the PCBA processing process is built on the PCB board, and all the following processes are placed on the PCB board operation, so the quality of the PCB determines the quality of the entire PCBA, so what aspects of the PCB have an impact on the PCBA?
1. Dirty board surface
The main reasons for the board surface contamination are high solid content of flux, too much coating amount, too high or too low preheating temperature, or too dirty PCB grippers of the conveyor belt, too much oxide and tin dross in the solder tank, etc.
The main solution: select the appropriate flux; control the amount of flux coating; control the preheating temperature; check the cleaning effect of the automatic cleaning of the PCB jaws and take measures; timely clean the oxide and tin dross on the surface of the solder tank.
Second, the white line leftover
White residue is commonly known as hoarfrost. Although it does not affect the surface insulation resistance, the customer does not accept it.
Solution: first use flux, then wash with solvent; if it cannot be cleaned, it may be due to aging of the flux, or exposure to the air to absorb water vapor, or due to the high moisture content in the cleaning agent (solvent), or the flux and cleaning If there is a mismatch between the fluxes, the supplier should be asked to assist in solving or replacing the flux and cleaning agent.
Three, PCB deformation
PCB deformation is mainly caused by the large-scale PCB quality or the uneven layout of components
When designing the PCB, try to make the components evenly distributed, and design the support belt in the middle of the large-size PCB (design a 2～3mm wide non-placement area); or use a mass-balanced tool to press on the PCB where the components are scarce, and realize it during soldering Mass balance.
These three points should be paid extra attention to when making PCBA. Improper handling will directly affect the quality of PCBA. I hope this article can help you!
