Under the action of a complex and harsh working environment, the damage of the IGBT power module’s packaging interconnection structure is the primary failure mode. The crack propagation and the bonding interface and the bond point shedding in the bonding wires will seriously affect the device’s electrical interconnection function and heat dissipation ability, resulting in its performance degradation and failure. In this work, the formulation and application of a multiscale approach combined with a cohesive zone model (CZM) were proposed to investigate IGBT bonding wires’ crack propagation. Firstly, the cohesive force model’s principle considering fatigue damage accumulation is analyzed, and the degradation multiscale simulation method of the critical structure of the power module is studied. Secondly, further research on IGBT bonding wires’ degradation behavior is carried out based on the macro and micro scales. The IGBT power module key package structure’s defect evolution model is established to analyze the damage evolution process of the critical package structure. Finally, the accuracy of the model is verified by the experiment analysis. Such a multiscale, mechanism-based cohesive zone model offers a promising approach for modeling and understanding the rate-dependent fracture of IGBT bonding wire crack evolution.

This study proposes an advanced space radiation shielding design method that integrates multi-objective optimization with reliability evaluation to mitigate the impact of harsh space radiation environments on electronic systems. A genetic algorithm is employed to optimize multi-layer shielding configurations with respect to radiation dose reduction, mass efficiency, and structural thickness. To ensure practical applicability, a reliability evaluation framework incorporating uncertainty factors is developed, where shielding designs are considered acceptable when the risk confidence level (CL) remains below 5%. A case study simulating long-duration deep space missions demonstrates that the optimized five-layer shielding configuration reduces the radiation-induced failure rate by approximately 57%, enhancing the long-term reliability of core electronic components to 0.94 over a five-year mission. These findings validate the effectiveness of the proposed approach in supporting the development of reliable, lightweight radiation shielding for future space missions.