Strain-rate dependent influence of adherend stiffness on fracture load prediction of BGA solder joints

Fracture experiments with ball grid array (BGA) specimens having different adherend rigidities were performed under bending loads at intermediate strain rates (0.2-1 s−1) and a high strain rate of 30 s−1. A cohesive zone model (CZM) was established and the predictive capability of the model was assessed for the specimens with different rigidities. The predicted fracture loads were within 12% of the measured forces when the CZM parameters were obtained using specimens with a similar degree of constraint. This suggests that in many practical cases, the effect of adherend stiffness can be neglected in predicting the strength of BGA solder joints.