An experimental study on the impact behavior of multilayer sandwich with corrugated cores

This paper experimentally investigates multilayers corrugated core sandwiches under out-of-plane compressive impact loading. The manufacturing method of corrugated core sandwiches in our laboratory is presented at first and its mechanical behavior under quasi-static loading shows a good repeatability. A testing configuration on the basis of a 97 mm diameter and 8 m long Nylon Hopkinson pressure bar is proposed to host this large sandwich sample and to impose a nominal strain of 70% to multilayer sandwich samples of 45.5 mm long. High-speed imaging system provides their deforming modes and reveals the interactions between adjacent layers. Finally, testing results on 1060 aluminum corrugated core sandwiches are obtained under quasi-static and impact loadings. Significant rate sensitivity is observed and it can be reproduced by the numerical simulation. The bending of the interlayer plate is also observed, which contributes to reduce the force oscillation during successive folding.