Failure behavior of sandwich beams with glass fiber-reinforced epoxy/aluminum laminates face-sheets and aluminum honeycomb core under three-point bending

The failure behavior and energy absorption performance of aluminum honeycomb sandwich beams with glass fiber-reinforced epoxy/aluminum laminates (GLARE) face-sheets under three-point bending are experimentally and numerically studied. The experimental specimens consists of 2/1 (2 aluminum sheets and 1 glass fiber/epoxy laminates) GLARE and aluminum honeycomb core. The effects of core height (8 mm, 20 mm, 40 mm) and indenter shape (cylindrical indenter and flat indenter) on bending failure behavior are tested in quasi-static three-point bending. Six sandwich beam specimens (300 mm-long and 40 mm-wide) were prepared. The initial failure modes of GLARE sandwich beams are observed, i.e. core shear and indentation. The numerical model considering geometric nonlinearity is established by ABAQUS/Explicit software and its effectiveness is verified by the experimental results of specimens with the same size and loading conditions. The effects of geometric and material parameters on the load-carrying capacity and energy absorption of the GLARE sandwich beams are discussed in details. It is shown that increasing the face-sheet thickness, honeycomb wall-thickness, the ratio of the core height to span length and the elasticity effect of metal materials or reducing the side length of the honeycomb cell can improve the load-carrying capacity and energy absorption of GLARE sandwich beams. The work can provide the guidance for the design of the GLARE sandwich structure with honeycomb core.