In this study, dynamic explicit analysis was performed to examine the air-blast performance of various hybrid sandwich designs in terms of face plate deflections and energy dissipation capacity under the conventional weapons effects program (CONWEP) air-blast loads ranging from 3 kg to 8 kg trinitrotoluene for stand-off distance ranges from 150 mm to 200 mm. The blast resistance of honeycomb sandwich configurations was evaluated using steel honeycomb with different core topologies, crushable Al foam-filled steel honeycomb, and steel or steel with 3D Kevlar/polypropylene laminate employing fiber metal laminate (FML) front face. For an accurate prediction of the deformation mechanism of all steel parts, the Johnson-Cook (J-C) model was used. The composite failure criteria of Hashin, Puck, and Matzenmiller were implemented to accurately examine the fiber and matrix damage behavior. The novel hybrid design of the honeycomb sandwich structure’s blast resistance is improved by the employment of foam-filled honeycomb, an FML front face, and a circular honeycomb core. In comparison to other sandwich configurations, a novel designed hybrid sandwich construction composed of foam filled circular honeycomb with FML front facing and steel back facing (FCH-1KP0.5) achieved the highest blast resistance due to its lowest face deflection with the smallest plastic dissipation energy.

A novel hybrid composite honeycomb sandwich structure (HCHSS) and metallic honeycomb sandwich structure (MHSS) were developed to obtain realistic and blast resistance parameters for the consideration of blast loading. Hybrid composite square honeycomb sandwich structure (HCSHSS) and metallic honeycomb sandwich structure with different cores such as square, hexagonal, octagonal, and circular were modelled to obtain the target protection level (lowest deflection) for the vehicle armour structure. The Johnson-Cook and Donadon failure criteria were incorporated into finite element analysis (FEA) for MHSS and HCSHSS, respectively. For the progressive damage modelling of the HCSHSS, the Donadon criterion was implemented in ABAQUS/Explicit software as a user-defined subroutine. The HCSHSS showed the fibre failure, matrix failure and delamination modes of failure in composite laminates and the plastic deformation failure of the core and metal plates. The HCSHSS was shown to have excellent blast worthiness properties in comparison to the MHSS. The metallic circular honeycomb sandwich structure (MCHSS) was shown to have the minimum deflection of the top and bottom face plates as compared to the square, hexagonal and octagonal honeycomb sandwich structures. A novel HCSHSS has obtained the minimum deflection for both the top and the bottom face plates in comparison to the other MHSS.