Perforation Modes of Double-Layered Plates With Air Gap Struck by a Blunt Rigid Projectile

The failure modes of the perforation of double-layered or multi-layered plates may be quite different. Further experimental analyses are conducted on the perforations of single and double-layered Weldox E steel plates with air gap to discuss the different perforation modes. It indicates that, in case of higher initial striking velocity, the failure mode of the first layer plate is adiabatic shear plugging, whilst the failure mode of the second layer plate is adiabatic shear plugging or shear plugging as the striking velocity of the projectile slows down. It concludes that the final failure mode of the double-layered plates is the hybrid of shear plugging and adiabatic shear plugging.