Comparison of different quasi-static loading conditions of additively manufactured composite hexagonal and auxetic cellular structures

Auxetic cellular structures have the potential to revolutionise sandwich panel cores due their superior energy absorption capability. Because of negative Poisson's ratio, auxetics behave counterintuitively and contract orthogonally under an applied compressive force, resulting in a densification material vicinity load. This study investigates three compares absorbing characteristics in-plane axial loading conditions. Three unit cell topologies are considered; conventional hexagonal, re-entrant double arrowhead auxetic structures. The samples were additively manufactured using two different materials, Nylon carbon fibre reinforced composite alternative (Onyx). Finite element simulations experimentally validated out conditions (auxetic) structure is shown exhibit comparatively absorption. For material, Onyx, specific absorbed by geometry was 125% 244% greater than hexagonal (non-auxetic) respectively.