Experimental investigation into the synergetic damage of foam-filled and unfilled corrugated core hybrid sandwich panels under combined blast and fragment loading

Foam filling strategy has been demonstrated to owing the ability to improve the blast resistance of sandwich panels under bare blast loading. But it is unclear that the effect of foam filling for performance improvement of sandwich panels in response to combined blast and fragments loading. In this paper, the corrugated core sandwich panels with and without aluminum foam fillers were designed, fabricated and finally tested under combined blast loading. Main attention focused on the influence of stand-off distance, foam filler density and core configuration on the dynamic responses in terms of deformation modes and failure mechanisms. The perforation failure of target panels could be alleviated with the increase of stand-off distance. The increase of foam filler density hardly affected the deformation/failure modes of panels, but it could reduce the permanent deformation of core webs and front face sheet. Relative to unfilled sandwich panels, foam filling behavior is an effective way to relieve the debonding failure between face sheet and core webs. Overall, the performance of foam-filled sandwich panels under combined blast loading is mediocre. The failure mode of foam-filled sandwich panels would transform from localized plastic deformation mode under bare blast loading to catastrophic failure under combined blast loading.

Automated summary

This paper investigates the effect of foam filling on the performance of sandwich panels under combined blast and fragments loading. The experimental results show that increasing the stand-off distance can alleviate perforation failure, increasing the foam filler density can reduce permanent deformation of the panels, and foam filling can relieve debonding failure between the face sheet and core webs.