Low-velocity impact resistance of composite sandwich panels with various types of auxetic and non-auxetic core structures

This work describes the low-velocity impact behavior of composite sandwich panels with different types auxetic (negative Poisson’s ratio) and non-auxetic prismatic core structures. Sandwich have been manufactured carbon/fiber epoxy face sheets, polyurethane rigid foam or 3D printed PLA plastic cellular honeycombs head (hexagonal, re-entrant, hexachiral arrowhead). The material properties constituents determined via tensile compression tests. topologies same wall thickness number cells (39x4, except for topology). A striker a hemispherical tip is dropped on specimens speed 2.6 m/s. Explicit finite element (FE) models are validated by experimental results. Parametric numerical analyses using FE carried out energies 10, 20, 30, 40, 50, 60 76 J to identify best designs. results show that cores could advantages over ones at small deformation (impact energy equal 10 J) thanks larger contact surface higher structure. core, however, provides greater resistance absorption capability as increases due densification lower indentation during collapse. arrowhead-based in particular possess 25%, 13% 11% crash efficiency than other samples impacts J. lattice performance 20 30 J, also possesses configurations (except arrowhead core) case loading. As result, those mostly recommended applications involving under large deformations.