Configuration‐Dependent Flexural Behavior and Microwave Transmission of Woven Lattice Sandwich‐Ply

ABSTRACT

Sandwich‐ply laminated composite (SLC), constructed by stacking woven lattice sandwich‐ply (WLS), provides a potential route for the design of lightweight multifunctional load‐bearing structures. In this study, WLSs with different configurations were designed and fabricated to investigate their flexural behavior and microwave transmission. The results show that thickness, core‐pile orientation, and foam filling jointly govern the flexural response and failure mechanisms of WLS. Increasing core height shifts the failure of unfilled WLS from face‐dominated damage to core shear failure, while the core‐pile orientation controls the damage mode between the faces and core. Foam filling markedly improves stiffness and load‐bearing capacity, suppresses core shear deformation, and shifts damage toward face fracture, cracking, and indentation. The stiffness of thicker WLS increases by approximately 723%–5073% in the warp direction and 100%–2372% in the weft direction. The load‐mass ratio increases by up to 260% and 439% in the warp and weft directions, respectively, although it decreases for some thinner WLS specimens because of the associated mass increase. For WLS with thicknesses of 2.551–16.285 mm, the band‐averaged transmittance ranges from 93.4% to 96.6% over 2–18 GHz. Four SLC radomes were further designed and tested. Their theoretical, simulated, and experimental transmission responses show good agreement, indicating the potential to tailor the transmission characteristics and target operating frequency range through WLS configuration. These findings provide guidance for the integrated mechanical and microwave design of lightweight radome structures.