The stress strain analysis under the reverse load of the embedded baseplate micro-scale grid array welder

Established embedded substrate microscale ball grid array solder three point bending stress and strain finite element analysis model, analyzed the solder joint materials, spot diameter and the influence of the bending stress and strain of solder pad diameter, the results show that the torque load, the embedded type substrate microscale BGA solder joint array of maximum stress and strain are occurred to the periphery on the solder joint around the corner, and the maximum stress and strain in contact with the PCB side of the edge. When applying the same under torsion load: in SAC305, SAC387, 63 sn37pb, 62 sn36pb2ag four solder materials, adopting SAC387 solder joint maximum equivalent stress is the largest, 62 minimum bending stress sn36pb2ag material welds; When the diameter of the solder was reduced from 105 mu m to 80 mu m, the internal stress strain of the microscale CSP solder was decreased. When the diameter of the disc was reduced from 80 mu m to 60 mu m, the internal stress strain of the micro-scale welder was increased.