Solder paste printing defects and solutions in SMT chip processing process
In the SMT chip processing process, solder paste printing is very complicated, and it has very important significance for product quality. This article mainly discusses the common defects of solder paste printing.
Solder paste printing defects solutions:
Incomplete printing: The solder paste has insufficient viscosity and cannot be effectively attached to the PCB or the blade is worn;
①Replace the solder paste. When selecting the solder paste, the size of the solid metal particulates should be considered, and the particle size should be smaller than the opening size of the steel mesh;
②Regularly check and replace the scraper;
Solder skip, Non-wetting/false soldering: insufficient solder paste or unqualified PCB, easy to appear Solder skip, Non-wetting/false soldering;
①Choosing a well-known manufacturer of PCB board brands can reduce the probability of PCB board failure;
②In the soldering process, ensuring the uniformity of tin and controlling the amount of tin can prevent Solder skip, Non-wetting/false soldering;
③Rough and burr of soldering: low viscosity of solder paste or rough opening of steel mesh;
④Pay attention to the viscosity of the solder paste before selecting the solder paste;
In order to ensure the SMT process is good, after the SMT patch is completed, The strong enterprise will test the SMT, and the most commonly used testing equipment is the NDT X-RAY inspection equipment, which has strong penetrating power to ensure SMT 360° shows the problem of whether there is a defect.
Family of Industrial X-ray inspection machine & BGA rework station
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