Deformation‐Driven Electromagnetic Switching: A 3D ‐Printed Polylactic Acid‐Carbon Fiber Curved Metamaterial Absorber With Broadband Reversible Tunability

Reconfigurable electromagnetic systems demand lightweight, conformal, and passively tunable wave‐regulating devices, yet conventional metamaterial absorbers struggle to integrate curved adaptability with reversible broadband tuning. Here we report a deformation‐driven electromagnetic switching (DDES) curved metamaterial absorber, monolithically fabricated via FDM 3D printing of carbon fiber‐reinforced polylactic acid (PLA‐CF). Tuning the bottom cross‐structure angle enables reversible switching between transmission and absorption states via continuous evolution of equivalent electromagnetic parameters. The absorber delivers favorable transmittance in the transmission state, and achieves full‐band high‐efficiency absorption with low radar cross section in the absorption state. Surface copper loading further introduces frequency‐selective regulation, realizing low‐band high reflection while preserving strong absorption at higher frequencies. This work provides a material–structure integrated paradigm for 3D‐printed deformable metamaterials toward intelligent electromagnetic compatibility applications.