This study investigates the thermo-mechanical behavior and residual stress characteristics of friction stir welding (FSW) in an aluminum inverter housing using finite element analysis (FEA). FSW experiments were first conducted under various tool rotation and traverse speed conditions, and temperature histories were measured using K-type thermocouples. The optimal process condition was identified through tensile testing, and the heat input was estimated by comparing experimental and numerical results. The estimated heat source was incorporated into a transient thermal elasto-plastic analysis to evaluate deformation and residual stresses in an inverter housing model. The results indicated that residual stress distributions varied depending on the welding start position. In particular, when welding started at P3 (near thick ribs and bosses) residual stresses were reduced by approximately 30% compared to P1, owing to the higher local stiffness and enhanced heat dissipation that mitigated temperature gradients. Conversely, welding initiated at P1, a flat region with insufficient reinforcement, resulted in higher stress concentrations. These findings confirm that the welding start position significantly influences residual stress behavior in inverter housings and provide fundamental insights for developing residual stress control strategies in FSW of large-scale components.

This study presents the results of compression, drop impact, and vibration durability analyses conducted to evaluate the mechanical reliability of Battery Pack Cases (BPCs) in electric vehicle (EV) systems. BPCs are essential structural components that must endure compressive loads, impact forces, and vibrational fatigue. Finite Element Analysis (FEA) was applied to a representative BPC model to assess deformation, impact resistance, and vibration endurance. The results indicate that the BPC maintained integrity within yield strength limits under compressive loading and effectively absorbed energy under drop impact. Furthermore, Power Spectral Density (PSD) analysis identified stress concentration regions, providing insights for structural optimization. Overall, the findings support the development of lightweight and reliable BPC designs for advanced EV applications.

Ear clamps are components used to securely fasten pipes and hoses in various industrial applications. They achieve clamping force by inducing plastic deformation at the ear region during installation, which can lead to accumulated structural damage and affect fatigue life. Moreover, the fatigue life is influenced by the design shape of the ear. Therefore, in this study, tensile and fatigue tests were conducted on two types of ear clamps with different ear geometries. Finite element analysis (FEA) was performed to obtain the stress distribution around the ear region, and these results were correlated with the experimentally obtained fatigue life. Based on this correlation, an S-N curve for simulation-based fatigue life estimation was established. This approach confirms the possibility of predicting the fatigue life of ear clamps with modified geometries using only finite element analysis, without the need for repeated fatigue testing.