Dynamic Crushing Behaviors of Multi-Layered Gradient Honeycombs with Different Poisson's Ratios: A Finite Element Simulation

In this work, a new multi-layered gradient honeycomb (MGH) design was proposed by filling structure layer with different Poisson's ratio configurations (e.g., positive, zero and negative Poisson's ratio) from the perspective of coupling the deformation characteristics with each other to improve in-plane dynamic properties and control energy absorption capacities. The dynamic behaviors and energy-absorbing characteristics of the MGHs under in-plane impact loadings were investigated by using explicit dynamic finite element (FE) simulation. This paper mainly focused on the effects of multi-layered gradient arrangements and impact velocities on the dynamic Poisson's ratios, dynamic plateau stresses, crushing load uniformities and specific energy absorption of the MGHs. A semi-empirical formula for the plateau stresses of the MGHs was presented. It was shown that through the proper choice of multi-layered arrangements, the MGHs can effectively improve the dynamic crushing behaviors and control energy absorption capacities. In addition, the dynamic shock enhancement of the MGHs was also investigated by introducing the uniformity index.