Composite structures with integrated electrothermal de-icing and broadband radar absorbing capabilities: Design, fabrication and characterization

Anti-icing/de-icing and radar absorbing (RA) performances are indispensable for stealth aircraft composite components such as wing leading edges and air intake lips. The conductive layer used for electrothermal de-icing, however, severely disturbs the impedance matching of internal absorbing structures, causing a key contradiction in multifunctional integrated design. This work proposes patterned carbon nanotube (CNT) films for Joule heating and designs multilayer patterned resistive films (PRF) to achieve broadband electromagnetic impedance matching. Multifunctional plate specimens and wing segment structures were fabricated by vacuum-assisted curing (VAC), and systematically evaluated through de-icing tests and radar cross section (RCS) measurement. The specimen delivers stable heating performance under variable voltages and excellent broadband RA ability with reflectivity below −11.3 dB within 2–18 GHz. Icing wind tunnel results verify that an approximately 0.5 mm initial ice layer on the wing leading edge was removed within 48 s under continuous icing conditions at −10 °C and 80 m/s. Compared with the metallic counterpart, the multifunctional wing segment achieves an RCS reduction of approximately 13 dB at typical pitch angles. This study provides a feasible innovative technical route for composite structures integrating electrothermal de-icing and broadband radar absorption.