Analysis of the Causes of Solder Joint Failure in PCBA production

With the development of miniaturization and precision of electronic products, the density of PCBA processing and assembly used by patch processing plants is getting higher and higher, and the solder joints in the circuit boards are getting smaller and smaller, and the mechanics and electricity they carry. And the thermodynamic load is getting heavier and heavier, and the reliability requirements are increasing. However, in the actual processing process, PCBA solder joint failure will also be encountered, and analysis is needed to find out the cause and avoid the occurrence of solder joint failure again.


The main reason for the failure of PCBA processing solder joints:


1. Poor component leads: plating, contamination, oxidation, coplanarity;


2, PCB pad defects: plating, pollution, oxidation, warping;


3. Solder quality defects: composition, impurities exceeding the standard, oxidation;


4, flux quality defects: low solderability, high corrosion, low SIR;


5. Process parameters control defects: design, control, equipment;


6, other auxiliary material defects: adhesives, cleaning agents.


PCBA solder joint reliability improvement method:


For the reliability test of PCBA solder joints, including reliability experiments and analysis, the purpose is to evaluate and identify the reliability level of PCBA integrated circuit devices, and provide parameters for the reliability design of the whole machine; on the other hand, it is to Improve the reliability of solder joints during PCBA processing. This requires the necessary analysis of the failed product, find the failure mode, and analyze the cause of the failure. The purpose is to correct and improve the design process, structural parameters, welding process and improve the yield of PCBA processing. PCBA solder joint failure mode is very important for the prediction of cycle life and is the basis for building its mathematical model.