Dynamic mechanical behaviour and energy absorption of aluminium honeycomb sandwich panels under repeated impact loads

Sandwich structures are widely applied in the field of marine structure lightweight design and impact protection due to their excellent mechanical properties. In this paper, the dynamic mechanical behaviour and energy absorption characteristics of aluminium honeycomb sandwich panels (AHSPs) under repeated impact loadings are investigated. A three-dimensional elastoplastic finite element model of AHSP under repeated impact loadings is established by using the commercial software ABAQUS Explicit. The accumulation processes of plastic deformation, the impact force-displacement curves as well as the energy absorption performances are numerically calculated. Besides, the repeated impact experiments of AHSPs were conducted by using the drop-weight impact testing machine INSTRON CEAST 9350. Furthermore, the influences of geometrical parameters on the dynamic behaviours of AHSPs under repeated impact loadings are further performed. Results show that the numerical calculated results are in good agreement with the experimental results. With the increase of the repeated impact numbers, the bending deflections of both top and bottom face sheets of AHPSs accumulate gradually, the compressive deformations of the honeycomb cores enlarge gradually and finally the densification phenomenon appears. The deformation mode of bottom face sheet experiences the mode transition from the global bending deformation model to the coupling deformation mode of the global bending deformations and the local indentations.