Design and Fabrication of a Carbon Fiber Reinforced 3D Woven Honeycomb Core

A carbon fiber reinforced honeycomb core was designed and fabricated using the continuous 3D woven process, which has advantages including more automatic fabrication, more continuous inter-layer connection and wider design space compared to conventional processes such as tailor-folding. The weaving-stretch method employed in this carbon fiber 3D woven honeycomb (3DWH) preform was rarely reported in pertinent literatures. A finite element model is developed to explore mechanical and thermal stability behavior of the 3DWH cores, and an optimized process and geometric parameters are obtained by a parametric investigation. Simulation results are validated based on some standard tension and CTE tests. The final optimized 3DWH core has several excellent properties incorporating a low density of 0.12 g/cm³, a low CTE of 1.192 × 10^–6/K, a high out-of-plane compression strength of 10.89 MPa, a high L-direction shear strength of 1.13 MPa and a side length of 12.7 mm, which indicates a great potential in lightweight and a high thermal dimensional stable structure.