4D‐Printed Intelligent Electromagnetic Materials for Adaptive Microwave Stealth and Multispectral Camouflage

Increasingly complex and dynamic applications demand intelligent and adaptive electromagnetic (EM) stealth and multispectral camouflage materials with self‐perception, actuation, and regulation capabilities. However, currently available EM materials with predesigned structure and confined EM performances cannot satisfy the diverse dynamic requirements. Herein, we report a general strategy to engineer intelligent reconfigurable EM materials by encoding programmable structures into liquid crystal elastomers with functional coating by topological 4D printing. The stimulus‐response structural reconfiguration establishes distinct EM‐wave interaction regimes and expands the accessible design space for EM functions, enabling the adaptive modulation of EM characteristics and multispectral camouflage. The proposed hypothesis is validated by constructing different reconfigurable structures with versatile functions. For example, the Miura‐origami configuration undergoes spontaneous folding under external stimuli, delivering reversible and seamless modulation from total reflection to broadband absorption (4.49–18 GHz, −21.4 dB). Moreover, reversible and adaptive switching between signal transmission and electromagnetic interference shielding is also achieved via a flower‐shaped “quasi‐Faraday cage”. Combined with outer functional coatings, it affords multispectral camouflage in dynamic and complex environments. Therefore, this work offers a feasible and versatile design route to develop reliable and self‐adaptive microwave stealth and multispectral camouflage materials for next‐generation intelligent systems.