Effects of initial defect on axial compressive strength of honeycomb Core

In this paper, the behavior of honeycomb core with initial defect, under compressive force along the axis of cells is investigated experimentally and numerically. The material is Al3105-H25 with the cell size of 17.32mm and the thickness of 0.074mm. The samples are 5×5 cells. For creating the initial defect, one cell was cut from the middle of each sample and the effects of this eliminated cell, on the structural behaviour are examined. The samples were tested between two compressive plates which were actuated by a displacement controlling system. The FE simulations were done by LSDYNA 971. In the simulations, two different approaches were used. In the first approach, the dimensions and the thickness of cells were measured and the mean values were selected. In the second approach, the actual dimensions and thickness of each cell was considered. It is concluded that, in the case of an existing defect, such as the loss of one cell, honeycomb core does not lose its total strength under compressive forces, but the loading capacity is decreased by the percentage of eliminated material plus a few percent. Also, non-homogeneous deformations were observed in cells with unsupported wall. The FE results are in an acceptable conformance with experimental results.

کلیدواژه ها:

Honeycomb core ، Compressive strength ، Crushing ، Buckling