Numerical and experimental study on hybrid sandwich panels subjected to impact loads

This work aims to study the damage of several panels made of sandwich composite material through impact tests at low speed and then subjected to tensile tests. In particular the aim has been the study of parameters correlated to damage like deformability due to low speed impact and the deflection of the panel (impact depth); with the help of a valid numerical model. Four different configurations of panels have been studied that differ in the thickness of the outer layers and the core. The composite material sandwich treated in this work, is made of two sheets: an external sheet of austenitic stainless steel 316L with a nominal thickness from a minimum of 0.135 mm to a maximum of 0.49 mm and a core constituted by a sheet of polyolefin with a thickness of 0.6 mm or 0.3 mm. These sheets are composed of a mixture of polymers, such as polypropylene (PP) and polyethylene (PE), with addition of talc (Mg3Si4O10 (OH)2), rutile (TiO2) and barite (BaSO4). Adhesive is used as a commercial epoxy (koratacr FL 201).