The energy

This paper investigates the compression properties and energy-absorbing characteristics of a carbon fiber-reinforced honeycomb structure manufactured using the vacuum-assisted resin transfer molding method (VARTM). The composite core materials were manufactured using a machined steel baseplate onto which hexagonal blocks were secured. A unidirectional carbon fiber fabric was inserted into the slots and the resulting mold was vacuum bagged and infused with a two-part epoxy resin. After curing, the hexagonal blocks were removed, leaving a well-defined composite honeycomb structure. Samples were then cut from the composite cores and inspected in an X-ray computed tomography machine prior to testing. Mechanical tests on the honeycomb structures yielded compression strengths of up to 35？MPa and specific energy absorption values in excess of 47？kJ/kg. When normalized by the density of the core, the resulting values of specific strength were significantly higher than those measured on traditional core materials. The unidirectional cores failed as a result of longitudinal splitting through the thickness of the core, whereas the multidirectional honeycombs failed in a combined splitting/fiber fracture mode, absorbing significantly more energy than their unidirectional counterparts. Increasing the weight fraction of fibers served to increase the strength and energy-absorbing capacity of the core. Finally, it was also shown that introducing a chamfer acted to reduce the initial peak force and precipitate a more stable mode of failure