Comparative mechanical performance of honeycomb core structures fabricated via fused deposition modeling and 3D woven composite processing

Abstract

Honeycomb cores are critical for high-performance sandwich composites, yet their mechanical efficiency is highly dependent on the manufacturing method. This study presents a direct comparison of hexagonal honeycomb cores (9 cells, 20 mm height) fabricated via fused deposition modeling (FDM) of ABS and 3D weaving of E-glass yarns followed by epoxy infusion using vacuum-assisted resin infusion molding (VARIM). Identical cell geometries were tested under flatwise compression, edgewise compression, three-point bending, and low-velocity impact. Mechanical properties were normalized by mass and volume to assess specific structural efficiency. Results show that 3D woven honeycombs exhibit significantly superior specific strength, stiffness, and energy absorption across all loading conditions compared to FDM-ABS counterparts. The superior performance stems from continuous yarn interlacement, enabling progressive buckling and mixed-mode collapse with excellent damage tolerance. In contrast, FDM cores suffer from brittle interlayer delamination and rapid crack propagation due to weak interlayer bonding. These findings establish 3D weaving as a superior route for lightweight, high-performance honeycomb cores in weight-critical applications.