Numerical Investigation for Bending Behavior of Hybrid Core Composite Sandwich Structure

Abstract This study provides a numerical study of the bending behaviour of hybrid-core composite sandwich panels being modeled using finite element method (FEM) using the software ANSYS Workbench 17 R1. This work emphasizes the use of core materials with well-defined mechanical response mechanisms to achieve optimum structural behavior as a way to advance the stiffness-to-weight efficiency and potency of the material for various high-performance engineering applications. The four sandwich core configurations that were modeled and analyzed under the same three-point bending condition were: (i) a conventional PVC foam core, (ii) a carbon/epoxy corrugated core, (iii) a hybrid corrugated core filled with polyurethane (PU) foam, and (iv) a hybrid corrugated core filled with PVC foam. Numerical findings showcased that the hybrid design with PVC foam gave the best mechanical behavior characterized by moderate equivalent stress (≈258 MPa), balanced elastic strain (≈0.022 mm/mm) and least total deformation (≈0.485 mm). Higher mechanical compatibility between the PVC foam and the corrugated composite structure was apparent, therefore, enabling effective stress transfer and stabilizing deformation behaviors. In contrast, the mismatched stiffness of the components in the PU-filled hybrid core resulted in significant strain and base instability, while the carbon-corrugated and neat PVC foam designs exhibited either localized high stresses or an undesirable brittle failure behavior. As viewed from a materials engineering perspective, the results presented here demonstrate that performance in terms of structural stability and durability of sandwich composites is critically dependent on core/textile morphology and material characteristics. The corrugated + PVC foam hybrid provides a good balance between rigidity, toughness, and lightweight properties and is ideal for aerospace, marine, and structural pieces where strength-to-weight is critical, and flexural energy absorption is required.