Enhanced Specific Energy Absorption in Honeycomb Structures With Novel Spiral Reinforcement and Foam Filling

This study introduces a novel honeycomb structure with enhanced specific energy absorption, wherein the internal cell walls are reinforced with a hexagonal spiral pattern. Additionally, the effect of incorporating rigid polyurethane foam into the void spaces between the honeycomb cells under quasi‐static loading conditions was evaluated. In this research, following modeling, reinforced and traditional honeycomb structure specimens were fabricated using FDM 3D printing with PLA+ material. Subsequently, the void spaces within the cells were filled with polyurethane foam. The specimens were then subjected to in‐plane loading. Results indicated that the reinforced honeycomb structure absorbed 503 and 700 J of energy in empty and foam‐filled states, respectively, with specific energy absorptions of 4.53 and 5.03 kJ/kg. These values represent increases of 159% and 138% in energy absorption and 116% and 100% in specific energy absorption, respectively, compared to the corresponding traditional honeycomb structure. This demonstrates that the innovative design presented in this research, coupled with the foam filling of the honeycomb voids, leads to a significant enhancement in specific energy absorption. Thus, the spiral‐reinforced, foam‐filled honeycomb structure can replace traditional honeycomb structures in the core of energy‐absorbing sandwich panels.