Dynamic cushioning energy absorption of paper composite sandwich structures with corrugation and honeycomb cores under drop impact

The paper composite sandwich structure with corrugation and honeycomb cores has been widely used in civil and national defense industries, and the cushioning energy absorption characteristic is a key indicator to evaluate the performance of this composite structure. Therefore, this paper is focused on the influences of honeycomb thickness on the shock acceleration response and deformation characteristics to analyze cushioning energy absorption performance of the composite structure by various experimental tests. The experimental result shows that the paper corrugation layer firstly comes into crushed, and then the paper honeycomb layer is crushed. Additionally, the large honeycomb thickness may cause the secondary collapse of paper honeycomb layer. Under the same impact energy or impact mass, the cushioning energy absorption of the single-sided composite sandwich structure is better than that of the double-sided structure with the same honeycomb thickness. However, the impact resistance of the double-sided composite structure is better than that of the single-sided structure. For the paper composite sandwich structures with the honeycomb thicknesses 10, 15, 20, and 25 mm, the increase of honeycomb thickness would decrease the cushioning energy absorption of the whole structure under the drop impact with low energy. However, under the drop impact with high energy, the influence of honeycomb thickness on cushioning energy absorption is contrary. For the paper composite sandwich structure, the specific energy absorption, unit volume energy absorption, and stroke efficiency for the honeycomb thicknesses 10, 15, 20, and 25 mm are higher than those for the honeycomb thickness 70 mm. Therefore, the low honeycomb thickness is more advantageous for the cushioning energy absorption of paper composite sandwich structure.