Preparation and properties of three‐dimensional hexagonal honeycomb woven composites with superior electromagnetic wave absorbing and load bearing performances

Abstract With the advent of the 5G era, electromagnetic pollution has been increasingly serious. Structural electromagnetic wave (EW) absorbing composites play a key role in both civil and military applications. However, the laminated plate structure and laminated honeycomb structure EW‐absorbing composites were prone to delamination and low EW absorbing performance. To enhance the EW absorption and mechanical properties of composite materials, this study successfully developed a novel three‐dimensional hexagonal honeycomb woven composites (3D‐HHWC). 3D‐HHWC with a three‐dimensional hexagonal honeycomb woven fabric (3D‐HHWF) as the reinforced materials was manufactured by the vacuum‐assisted resin transfer molding (VARTM) process with epoxy resin, carbon black (CB), multi‐walled carbon nanotubes (MWCNTs), and carbonyl iron powder (CIP) as functional materials. The EW absorption performance and bending mechanical properties of 3D‐HHWC with different structural parameters were compared and analyzed. The test results demonstrated that the 3D‐HHWC (H 2‐3 ) achieved a remarkable minimum reflection loss of −38.1 dB with the effective electromagnetic absorption band (EAB) 13.8 GHz. Additionally, CST provided a clear explanation of the electromagnetic field distribution elucidating the mechanism for EW absorption. While the 3D‐HHWC (H 2‐3 ) had a maximum bending load 6603.9 N without obvious delamination phenomenon. Furthermore, finite element simulation clarified internal stress distribution explaining the failure mechanisms. In conclusion, the 3D‐HHWC exhibited outstanding EW absorption and mechanical properties for widespread application in military and aerospace fields. Highlights The 3D‐HHWC was formed by VARTM process with epoxy resin, CB, MWCNTs, and CIP. The 3D‐HHWC had excellent EM performance with RL min −38.1 dB and EAB 13.8 GHz. CST provided a clear explanation of the electromagnetic field distribution. The 3D‐HHWC had a maximum bending load 6603.9 N without obvious delamination. FEM clarified internal stress distribution to explain the failure mechanisms.