Novel Perforated Design Strategy for Honeycombs with Enhanced Specific Stiffness and Reduced Stress Concentration

A novel perforated honeycomb structure (PHS) was proposed by perforating the cell walls of the regular hexagonal honeycomb structure (RHHS) along the out‐of‐plane direction. Theoretical models for the in‐plane elastic constants of the PHS were established based on a simple energy approach with fully considering the stretching, shearing, and bending of the cell walls, as well as the secondary bending moment due to shear. Finite element (FE) simulations and experiments were carried out to verify the theoretical models, demonstrating an excellent agreement. The effects of geometrical parameters, such as the ratio of circular hole diameter to cell wall thickness ( D / t ) and circular hole numbers ( n ), on the in‐plane elastic properties of the PHS were further analyzed. A comparison of the in‐plane stiffness of the RHHS and the PHS under the same relative density was presented. The stress distribution in the structures under uniaxial compression and shear loading was also fully discussed. The results show that the PHS exhibits greater in‐plane specific stiffness than the RHHS. Furthermore, the perforation design strategy proposed can significantly reduce the peak stress, thereby reducing the stress concentration. Remarkably, the perforated design proposed is applicable to all two‐dimensional honeycomb structures.