The mechanical properties of laminated motor cores strongly influence the NVH performance of electric drives. Two commonly used joining techniques, glue lamination and welding/interlocking, result in distinct structural behaviors that must be carefully considered in predictive modeling. Glue-laminated cores rely on adhesive bonding distributed across the lamination plane, producing relatively uniform stiffness and increased damping, which can be homogenized effectively using transversely isotropic assumptions within a unit cell (RVE) framework. In contrast, welded or interlocked cores introduce localized mechanical connections, such as spot welds, contact and connecting spots, that create strong stiffness discontinuities and alter load transfer between laminations. These connections increase out-of-plane stiffness but reduce damping, resulting in higher natural frequencies and more pronounced vibration transmission compared with glued cores.

This study extends the RVE-based homogenization method to account for these differences by explicitly representing the connection mechanism in the unit cell. For glue-laminated cores, the adhesive coverage is modeled statistically to achieve an even distribution. In contrast, for welded/interlocked cores, discrete welds or mechanical interlocks are introduced into the RVE geometry, capturing spacing, size, and geometry effects. Finite element simulations are performed to derive effective elastic and shear moduli for each case, and the results are validated against production motor core measurements. Excellent agreement confirms the predictive capability of the proposed framework.

By clarifying the distinct modeling needs of glue versus welded/interlocked laminations, this work provides a unified methodology for accurate property prediction, enabling more reliable NVH analysis and guiding joining-technology choices in motor design.