Crushing behaviour of corrugated tilted honeycomb core inspired by plant stem

Abstract

In this study, a new corrugated tilted honeycomb (CTH) core for sandwich structure is proposed by implementing the corrugated and tapered shape inspired by plant stems. Its crushing responses and energy absorption capacity are numerically investigated by using finite element software LS-DYNA. This study aims to propose an effective energy-absorbing core with a high energy-absorbing capacity and high crushing force efficiency. The crushing and energy absorption efficiencies of the proposed CTH cores are evaluated by comparing them with those of the commercially available cores such as square honeycomb core and aluminium foam of the same mass. The crushing performances of each core are evaluated by using the key indicators of the energy-absorbing structure such as the peak crushing force (PCF), mean crushing force (MCF), crushing force efficiency (CFE), and the specific energy absorption capacity (SEA). The effects of the crushing speed, tilted angle, and relative density on the crushing behaviour of the proposed CTH core are also investigated. It is found that under various crushing speeds, the proposed CTH core has a lower PCF, a higher MCF, CFE, and SEA than the conventional square honeycomb core and aluminium foam of the same mass. Furthermore, the CTH core has higher CFE and SEA than most of the existing structural forms of cores with similar relative density. The CTH core with two corrugations (C2) has a significantly improved SEA, which is four times higher than aluminium foam, up to 142% higher than the primitive structure, and 46% higher than the square antiprism structure, showing an excellent performing core for the energy-absorbing sandwich structures.