Evaluation of Impact Resistance of Honeycomb Sandwich Panels by Compressive Properties of Honeycomb Cores

Honeycomb sandwich panels are kind of composite panels constructed by adhering thin surface plates such as CFRP laminates or metal sheets with honeycomb cores made of aluminum or aramid materials. Honeycomb sandwich panels have light-weight and high strength performances. So they are widely used in many fields such as the transportation equipment field, especially for light-weight mainly required aerospace field. On the other hand, the merit of the honeycomb sandwich panels is effective only in the limited environment. For example, it is strong only when uniform loads are applied on the surfaces of the panels, while honeycomb cores show vulnerability with local concentrated loads applied. Under concentrated loads, it is possible that the strength of whole panel should be reduced due to local buckling failure inside the honeycomb core. However, no data on local buckling properties of honeycomb structures are widely publicized and testing methods are not clearly stipulated. Therefore, the purpose of this study is to grasp the local buckling tendency of honeycomb structures affected by design variables like foil thickness, cell size and specimen size (length, width, height dimension) of honeycomb structures. Compression tests on honeycomb sandwich panels having different design variables are executed to examine buckling performance under local impact loading.