Design of Honeycomb Mesostructures for Crushing Energy Absorption

This paper presents the energy absorption properties of hexagonal honeycomb structures of varying cellular geometries under high speed in-plane crushing. While the crushing responses in terms of energy absorption and densification strains have been extensively researched and reported, a gap is identified in the generalization of honeycombs with contr'olled and varying geometric parameters. This paper addresses this gap through a series of finite element (FE) simulations where the cell angle and the inclined wall thickness, are varied while maintaining a constant mass of the honeycomb structure. A randomly filled, nonrepeating design of experiments (DOEs) is generated to determine the effects of these geometric parameters on the output of energy absorbed and a statistical sensitivity analysis is used to determine the parameters significant for the crushing energy absorption of honeycombs. It is found that while an increase in the inclined wall thickness enhances the energy absorption of the structure, increases in either the cell angle or ratio of cell angle to inclined wall thickness have adverse effects on the output. Finally, the optimization results suggest that a cellular geometry with a positive cell angle and a high inclined wall thickness provides for maximum energy absorption, which is verified with a 6% error when compared to a FE simulation.