V-air bending and springback of symmetrical sandwich panels with three-layer metallic foam cores

This study employs theoretical methods and finite element simulations to study the V-air bending performance and springback of symmetrical sandwich panels with three-layer metallic foam cores. Based on classical plate theory and elastic-linear hardening constitutive models, material regions with distinct mechanical states are delineated, yielding the relationship between neutral surface radius and bending moment. An analytical model for the V-air bending performance and springback of symmetrical sandwich panels with three-layer metallic foam cores is established. Numerical methods are employed to study the force-displacement relation and springback angle-displacement relationship of the sandwich panels using software ABAQUS. The analytical results are compared with finite element results, and agree well with numerical results. Further, the influences of the density distribution within the core layer and thickness ratio on the V-air bending performance and springback of sandwich panels are discussed. It is found that the density factor and thickness factor are positively correlated with downward force and springback angle, with the influence on downward force being more significant. Particularly, for the case of constant total thickness and layer density, increasing the thickness factor has a smaller effect on the downward force and springback angle than decreasing the thickness factor. The present analytical model effectively predicts the V-air bending processing and springback characteristics of symmetrical sandwich panels with three-layer metallic foam cores.