Stress and Strain Analysis of QFN Solder Joint under Torsional Loading

The 3D finite element analysis model of QFN solder joints was established. The influence of various factors on the torsional stress and strain of QFN solder joints under the same torsional loading conditions was studied by single factor analysis. SAC305 solder joint materials were selected for solder joint materials and analyzed. The effect of the point length, the width of the solder joint and the height of the solder joint on the torsional stress and strain of the solder joint obtained the stress and strain distribution of the QFN solder joint. The results show that the maximum stress of the maximum stress in the QFN solder joints appears on the side in contact with the PCB board when the torsional load is applied to the same displacement load. As the height of the solder joint increases, the maximum torsional stress and strain in the solder joints As the length of the solder joint increases, the maximum torsional stress and strain in the solder joint increases; as the solder joint width increases, the maximum torsional stress and strain in the solder joint decreases.