Crashworthiness of Ultrathin Aluminum Honeycomb Structure

This study is aimed at designing, analyzing, and demonstrating the energy-absorbing capacity of ultra-thin honeycomb structures subjected to the quasi-static axial loading, and also to analyze their crashworthiness. The primary objectives of the study encompass the examination of the crushing response of aluminum honeycomb structures in the out-of-plane direction, utilizing a universal testing machine. Two different cell sizes (i.e., 12 and 19 mm) with constant cell wall thickness and nodal height were investigated for a honeycomb specimen. To carry out numerical simulations, commercially available ANSYS/LS-DYNA^® code was used. The honeycomb core was meshed with the Belytschko-Tsay (ELFORM2) shell element, and the material model MAT024 (Piecewise_Linear_Plasticity) was used for assigning the material to the honeycomb core. Crashworthiness characteristics like peak crushing load, mean crushing load, total energy absorption, specific energy absorption, and modes of deformation were studied for the honeycomb core under out-of-plane loading condition. Furthermore, to quantify the impact of changing the cell size on the honeycomb specimen’s ability to absorb energy across various deformation regions, a parametric study was performed using numerical method. The results revealed that the smaller cell size (3.2 mm as investigated in this study) honeycomb structure showed higher resistance to crushing in terms of higher crushing load and total energy absorbing capacity.