ENERGY ABSORPTION DURING PROJECTILE PERFORATION OF LIGHTWEIGHT SANDWICH PANELS WITH METALLIC FIBRE CORES

摘要

This paper documents an experimental and numerical study of energy absorption in lightweight sandwich panels with metallic fibre cores, when perforated by hardened, spherical steel projectiles. The sandwich panels are manufactured entirely from austenitic stainless steel (type-304). The faceplates are 0.4 mm thick and the core material, composed of a bonded network of slender metallic fibres, is approximately 1-1.5 mm thick. The sandwich panels have been impacted over a range of impact velocities and the absorbed energy has been measured. Simulations were conducted using the explicit finite element code in ABAQUS/CAE. The faceplates were modelled using the phenomenological plasticity model of Johnson & Cook, coupled with a strain rate-dependent, critical plastic strain fracture model. The core was modelled as an anisotropic crushable foam material using a VUMAT subroutine. Failure of the core material was captured using a quadratic shear stress failure criterion. The agreement between the simulations and the experiments is found to be good in terms of failure mode. The absorbed energies are also in good agreement.