Energy absorption characteristics of a lightweight auxetic honeycomb under low-velocity impact loading

Auxetic honeycombs have been extensively studied due to their unique mechanical properties. In this paper, the dynamic response of WSH (The windmill-like configuration composed of stars and hexagons) honeycomb is systematically studied by theoretical calculations, numerical simulations, and experimental methods. The static and dynamic plateau stresses of WSH honeycombs are calculated, and critical velocities leading to different deformation modes of WSH honeycombs are derived. Finally, the gradient design of WSH honeycombs is carried out. And the dynamic response of the gradient WSH honeycombs is explored through numerical simulations. Under low-velocity impact loading, WSH honeycombs have better energy absorption capacity than conventional honeycombs. Both the concave angle gradient design and thickness gradient design can further enhance the energy absorption performance of WSH honeycombs.