A multi-layer square frustum metamaterial for ultra-broadband electromagnetic absorption based on carbonyl iron powder/carbon fiber composites

Ultra-broadband electromagnetic absorption has become a critical issue competing with the advanced broad-band electromagnetic detection systems. In this study, a novel metamaterial with periodic square frustums was designed and prepared, based on the carbonyl iron powder/carbon fiber/Resin composites. The electromagnetic parameters for each component of the meta-structure were determined by the ad-dition content of carbonyl iron powder and carbon fiber, and the prepared metamaterial with optimized electromagnetic and structural parameters realized efficient EM absorption (> 90%) in the frequency band of 3.5-40 GHz. Additionally, the electromagnetic absorption mechanism is believed to be attributed to the synergic result of the multiple electromagnetic loss modes and the improved impedance matching caused by the multi-scale structure. Therefore, the proposed metamaterial absorber realizes an ultra-broadband electromagnetic absorption with a coordinated optimization of electromagnetic parameters and meta -structure, which could be served as electromagnetic wave absorbing devices for broadband absorption applications.(c) 2023 Elsevier B.V. All rights reserved.