Research on Mechanical Properties of V-Type Folded Core Sandwich Structures

Abstract

A folded core is a three-dimensional configuration formed by folding a flat sheet of paper. Similar to foam and honeycomb, folded cores are widely used in aerospace as the cores for sandwich structures due to their excellent mechanical properties and light structural weight. In general, the core’s configuration is heterogeneous and anisotropic, while from a macroscopic point of view it is considered homogeneous. Analytical solutions of equivalent mechanical properties are generally obtained by equivalent methods and modified by numerical simulations due to the complexity of the configuration. We can find the best combination of a core’s parameters by using analytical solutions. The faceted regular folded configuration (RFC), consisting of repetitive identical cells, can be expanded to a plane. According to the principle of equivalent load-deformation, this article investigates the equivalent mechanical properties of the V-type folded core (VFC). The analytical solutions of Ez—equivalent elastic modulus in Direction z, equivalent shear modulus in Plane xz—Gxz, and equivalent shear modulus in Plane yz—Gyz have been obtained and verified by numerical simulations. In addition, the reliability of the equivalent mechanical properties is further demonstrated by the case study. By applying the analytical solutions, the optimization process of VFC can be simplified and sped up, which is of great engineering significance to the aircraft design process.