Micromechanical Model for Describing Intergranular Fatigue Cracking in an Innovative Solder Alloy

摘要: Fatigue of solder joints remains one the critical concerns in thermo-mechanical reliability high-power electronic systems. Several semi-empirical fatigue models based on effective material properties at macro-scale already exist, but have shown some limitations for providing accurate lifetime prediction scale microelectronic packages. Therefore, there is a need to enrich existing approaches by description failure mechanisms microstructure scale, taking into account important features alloy. In this study, 3D microstructure-informed model reproducing intergranular crack joint developed. The submodeling technique has been applied order only investigate zone joint. A global whole module first simulated obtain inputs submodel focused interest where expected develop. simultaneously makes use cohesive and crystal plasticity theories represent decohesion grain boundaries plastic slips grains joint, respectively. Simulations repeated loading package demonstrate how cracking occurs submodel. addition, it that propagation rate almost constant during time. This suggests an ability present approach give estimate entire extrapolating specific computed quantities from local model.