Sandwich plates with functionally graded metallic foam cores subjected to air blast loading

•Poor bonding results in larger transverse deflection of graded sandwich plates.•Higher relative density foam near loaded side achieves the best blast resistance.•Thinner top face-sheet and thicker bottom face-sheet is beneficial for plate design.•The graded sandwich plate has advantage over conventional sandwich plates.

The dynamic responses and blast resistance of all-metallic sandwich plates with functionally graded close-celled aluminum foam cores are investigated using finite element simulations, and compared with those of ungraded single-layer sandwich plates. Upon validating the numerical approach using existing experimental data and introducing the present computational model, different graded sandwich plates under air blast loading are analyzed in terms of deformation and blast resistance. The effects of face-sheet arrangements and interfacial adhesion strength between different foam layers are quantified. The results demonstrate that relative to conventional ungraded plates subjected to identical air blast loading, the graded plates possess smaller central transverse deflection and superior blast resistance, with further improvement achievable by optimizing the foam core arrangement. The blast resistance of both graded and ungraded sandwich plates subjected to the constraint of equivalent mass is also explored.