Statistical method of extracting assembly stresses in over-constrained solder-less press-fit pin technology for vibration reliability analysis

Abstract Solderless press-fit technology is increasingly favored over lead-free solder mountings due to cost-effective design benefits amid lead-free regulations. However, its over-constrained nature causes assembly issues and preload stress in pins, leading to fatigue failure under vibration. This paper extends previous research by presenting a method to evaluate the robustness of these assemblies under vibration-induced fatigue, considering assembly-induced stresses as static preload stress. The proposed statistical method uses Monte Carlo simulations to compute the distribution of pin failures due to fatigue, providing a comprehensive analysis that traditional worst-case FEA simulations cannot. This approach aids in identifying worst-case scenarios, predicting failure percentages, ranking designs, and improving design robustness through iterative feedback during the design phase.