Low Velocity Impact Behavior of Aluminum Honeycomb Structures

Impact behaviors of aluminum honeycomb sandwich panels (AHSPs) are investigated experimentally by using a drop weight test setup. The specimens of 12.7 mm cell size were tested by impacting at four different initial contact points, namely face center, corner, long edge and short edge of core cells, with two impactors of weights 5.25 kg and 11.9 kg, respectively. Dynamic nonlinear transient analysis was also carried out by a finite element simulation model developed based on continuum damage mechanics to account for nonlinear and elastoplastic behavior. The results revealed that while the impact behaviors of AHSPs were nearly the same for low impact energy, they were different for high impact energy. The peak resistance force of AHSPs was the highest for impact at the face center and the lowest for impact at the short edge of the core cells. The results of FE simulation revealed that the real time deformation produced fracture when the crack initiated and propagated to the honeycomb core from the facesheet.