Energy absorption and impact behavior of composite sandwich panels under high-velocity spherical projectile

In this research, the impact behavior and energy absorption of sandwich panels with composite foam cores under high velocity (50 -220 m/s) impact were experimentally investigated. The dynamic deflection of rear sheets was captured and analyzed using three dimensional digital image correlation technique with high-speed cameras. The effects of density, thickness and multi-layer of cores on the anti-penetration and energy absorption performance of sandwich panels were evaluated. The study results showed that the penetration could only produce the slightly local permanent deformation around the impact position for rear sheets. The plug and petalling were the typical failure modes of front and rear sheets, respectively. The increase in density and thickness of cores both could result in an obvious improvement in the ballistic limit velocity of panels. In addition, the energy absorption efficiency of panels could be effectively improved by increasing the thickness and density of cores. However, the effect of thickness of cores on the attenuation of energy absorption efficiency of panels was negligible under the same density of cores. Particularly, the multi-layer cores presented negligible effect on the anti-penetration and energy absorption performance of panels in this study.

Automated summary

The research showed that increasing the density and thickness of cores can significantly improve the ballistic limit velocity of sandwich panels and enhance the energy absorption efficiency. The effect of increasing core thickness on the energy absorption efficiency of panels was negligible under the same core density. Multi-layer cores had negligible impact on the anti-penetration and energy absorption performance of panels.