Broadband electromagnetic wave absorption and lightweight load-bearing design of sandwich structures with oblique corrugated channel cores

Aiming at the demand for structural–functional integrated designs with electromagnetic (EM) wave absorption and lightweight load bearing performances, an oblique corrugated channel sandwich structure (OCCSS) is proposed. The oblique corrugated channel is assembled from oblique corrugations, which are cut obliquely from straight corrugations. For EM wave absorption, glass fiber reinforced plastic (GFRP) and carbon fiber reinforced plastic are used for the face and back sheets, respectively, while the core is formed by GFRP and indium tin oxide (ITO) films. EM simulations and experimental tests indicate that the proposed OCCSS realizes broadband (4–18 GHz), wide-angle (0°–60°), and efficient (>85% absorptivity) EM wave absorption. The EM simulations demonstrate that the concentrated E-fields excited by the oblique corrugated channel enhance the efficiency of the current flow along the ITO films, which results in a 21% increase in the absorptivity of the OCCSS compared with that of a straight channel sandwich structure (SCCSS). The compressive performances of the OCCSS and SCCSS are investigated experimentally. The results show that the energy absorption per unit mass of the OCCSS is 43.2% higher than that of the SCCSS. The OCCSS demonstrates strong potential in engineering applications owing to its excellent EM wave absorption and load bearing performance, as well as potential thermal management capability.