Energy-absorption Characteristics of Nacre-inspired Carbon/Epoxy Composite Tubes under Impact Loading

In this study, the structural regularity of staggered and overlapped aragonite tiles in nacre was used to design novel carbon/epoxy composite tubes with improved energy absorption behaviors. Dynamic drop hammer impact tests were performed on both continuous square tubes (QC) and nacre-inspired composite (QD) tubes under different impact energies. The data suggested that impact energy of 1059.63 J resulted in an average crushed length of 49.87 mm for QC tubes and 37.86 mm for QD tubes, equivalent to 24% reduction. Moreover, the specific energy absorption (SEA) of QD tubes was about 36% higher than that of QC tubes. The fractographic analyses of the QD tubes revealed that the improved energy absorption performances were attributed to the crack deflection and parallel propagation of multiple cracks during the crushing process. These findings look promising for the design and fabrication of future passive security devices with advanced properties.