Energy absorption and failure mechanism of metallic cylindrical sandwich shells under impact loading

The dynamic response, energy absorption capability, and deformation and failure of clamped aluminum face-sheet cylindrical sandwich shells with closed-cell aluminum foam cores were investigated numerically by impacting the shells at central area with metallic foam projectiles in this paper. Typical deformation/failure modes and deflection response of sandwich shells, obtained from the experiments, were employed here to validate the numerical simulation. Numerical results indicate that the shock resistance of sandwich shells could be enhanced significantly by optimizing their geometrical configurations; the thickness of back face-sheet has a greater contribution than that of front face-sheet. Increasing of impact velocity and decreasing of face-sheet thickness, core relative density and curvature radius can enhance the energy absorption capability of sandwich shells. The initial curvature of sandwich shells may induce easily tearing failure along their circumferential directions. These findings can guide well the theoretical study and optimal design of metallic sandwich structures subjected to impulsive loading.