Dynamic compressive properties of reinforced and kirigami modified honeycomb in three axial directions

In this study, a novel kirigami modified honeycomb structure (KHC) made of aluminium sheets was developed to enhance the crashworthiness of the conventional honeycomb structures (HC) in all three directions. As one of the only commercially available modified honeycombs, reinforced honeycomb (RHC) was also included for comparison. The compressive properties of three types of honeycomb structures in three axial directions were tested under various loading rates and compared. It was demonstrated that the KHC significantly enhanced the crashworthiness in all three directions under all loading scenarios tested in this study. Under out-of-plane crushing, the initial peak crushing force of KHC was greatly reduced while maintaining a similar average crushing force as RHC and higher than that of HC. Under both in-plane crushing, KHC showed the improved crushing resistance without introducing a significant initial peak crushing force. Furthermore, the loading rate dependency of the initial peak crushing force of KHC was also considerably lower than that of HC and RHC under out-of-plane dynamic crushing. Overall, kirigami modification significantly improved the crashworthiness of conventional and reinforced honeycomb structures without notably complicating the manufacturing process or adding filler materials, especially in out-of-plane direction. • Dynamic crushing response of conventional, reinforced and kirigami modified honeycombs are experimentally investigated. • Energy absorptions are compared for three types of honeycombs at three loading directions. • Superior energy absorbing performance is demonstrated by kirigami modified honeycomb for all loading scenarios. • Loading rate dependency of three honeycombs along three axial directions is studied.