Dynamic failure of carbon fiber-reinforced plastics sandwich structures with polyvinyl chloride foam cores subjected to impact loading

The dynamic failure of carbon/epoxy sandwich plates with polyvinyl chloride foam core subjected to foam projectile impact is experimentally analyzed in this research. The effects of intensity of impact impulse, cores density, core thickness on the impact resistance of the composite sandwich plates in terms of deflection of rear sheets are also assessed. The 3D- digital image correlation technique is applied to measure the dynamic deformation of the sandwich plates. The results show that the carbon/epoxy sandwich plates exhibit more excellent impact resistance than aluminum sandwich plates with polyvinyl chloride cores at the similar area mass. The carbon/epoxy sandwich plates experience an obvious spring back, and only a slight plastic deflection can be observed after test. The failure modes of the sandwich plates include plastic deformation, fiber breakage, delamination, matrix crack, debonding, and compression of cores. The damage of plates become more serious with core density and core thickness decreasing, and impact impulse increasing, respectively.