A novel centresymmetric honeycomb composite structure

In this paper analytical and finite element (FE) simulations are carried out to calculate the in-plane Poisson's ratio and Young's moduli of a new centresymmetric honeycomb configuration under uniaxial loading. Opposite to similar re-entrant honeycomb structures studied in the past, the new re-entrant unit cell topology takes into account possible manufacturing constraints typical of production routes like Resin Transfer Moulding (RTM) or Rapid Prototyping (RP). The results obtained through the analytical and FE analysis show a significant decrease of the Poisson's ratio for the internal cell angle between -20 degrees and +20 degrees compared to the classical re-entrant configurations exhibited in literature. The results also show that the presence of edge corners in the unit cell honeycomb configuration gives rise to a cellular structure with enhanced flexibility compared to the classical centresymmetric one. The results obtained by the analytical model show good agreement with the Gibson and Ashby rib-bending model when the honeycomb configuration reduces to the theoretical layout without modifications due to manufacturing constraints. (C) 2005 Elsevier Ltd. All rights reserved.