Effect of foil thickness and cell size of honeycomb on energy absorption of aluminium honeycomb sandwich composite (Charpy Test)

Sandwich composites are special class of materials because of peculiar properties such as lightweight, high energy absorbing capacity, and high damping, etc. These properties make them suitable for their use in aerospace and marine industry. Generally, metal or FRP sheets are used as skin/face sheet and honeycomb, foam and balsa wood, etc. are used as core materials. The elastic properties of the honeycomb are the function of foil thickness and cell size. In the present study, the effect of parameters (Foil thickness and Cell size) of the honeycomb on the energy absorption capacity of the sandwich composite was investigated through experimental and numerical studies. Experiments were carried out on four sandwich composites having a variable combination of foil thickness, and cell size by using the Charpy ASTM E-23 machine. Further, numerical analyses were carried out using finite element (FE) software Abaqus. The experimental and numerical results were found to be in good agreement. The results show that energy absorption to mass ratio increases with the increase in foil thickness and with the decrease in cell size. For the improvement of energy absorption to mass ratio, the effect of change in the foil thickness is significant compared to that of change in cell size. Failure mechanism was discussed through numerical study. The impact force resisted by the sandwich composites was presented by using the impulse-momentum equation.