Frequency insensitive electromagnetic absorption core-shell sandwich structure with excellent electromagnetic damage tolerance

Abstract

The compatibility of broadband electromagnetic absorption and electromagnetic damage tolerance poses challenges to the regulation of electromagnetic response characteristics, which are typically restricted by the intrinsic dispersion of materials and strong resonant features of unit cell structures. In this work, triply-periodic-minimal-surfaces (TPMS) based gradient core-shell sandwich structure is proposed to address this challenge for its mathematical defined unique conductive pore structure. The reflection loss-frequency curve is less than −10 dB in 2–18 GHz frequency band, accompanied by two separate resonant absorption peaks at 2.4 GHz and 17.5 GHz. The reflection loss curve is insensitive to frequency in a wide frequency band of 4–14 GHz, using merely three kinds of absorbing materials. When the damage proportion is less than 40 %, effective electromagnetic absorption can be maintained in panel damage, core damage and penetrating damage modes, thanks to the extraordinary conduction-dissipation effect. Our study provides valuable insights for the design of damage tolerant electromagnetic absorption structures.