Foam core sandwich panels operate based on the principle of structural separation of load paths, where two high-strength face sheets (such as FRP, aluminum, or steel) are bonded to a lightweight core (XPS, PET, PU, PVC). The core’s primary function is not to carry tensile or compressive stress directly but to maintain the distance between the skins, significantly increasing the panel’s moment of inertia.
This configuration dramatically improves bending stiffness (D), which is proportional to the cube of the panel thickness. Compared to solid materials, sandwich structures achieve higher stiffness-to-weight ratios, making them ideal for applications like marine decks, wind turbine blades, and architectural panels.
Additionally, the foam core contributes to shear transfer, distributing loads evenly and preventing localized buckling. Different foam types (e.g., PVC vs PET) influence shear modulus, thermal stability, and fatigue resistance, making material selection a critical engineering decision.
