Manufacturing of a Magnetic Composite Flexible Filament and Optimization of a 3D Printed Wideband Electromagnetic Multilayer Absorber in X-Ku Frequency Bands

Abstract

With the multiplication of electronic devices in our daily life, there is a need for tailored wideband electromagnetic (EM) absorbers that could be conformed on any type of surface-like antennas for interference attenuation or military vehicles for stealth applications. In this study, a wideband flexible flat electromagnetic absorber compatible with additive manufacturing has been studied in the X-Ku frequency bands. A multilayer structure has been optimized using a genetic algorithm (GA), adapting the restrictions of additive manufacturing and exploiting the EM properties of loaded and non-loaded filaments, of which the elaboration is described. After optimization, a bi-material multilayer absorber with a thickness of 4.1 mm has been designed to provide a reflectivity below −12 dB between 8 and 18 GHz. Finally, the designed multilayer structure was 3D-printed and measured in an anechoic chamber, achieving −11.8 dB between 7 and 18 GHz. Thus, the development of dedicated materials has demonstrated the strong potential of additive technologies for the manufacturing of thin wideband flexible EM absorbers.

Review of Broadband Metamaterial Absorbers: From Principles, Design Strategies, and Tunable Properties to Functional Applications

“…In this section, we focus on summarizing the design strategies of BMAs, mainly including three core strategies, such as top‐down lithography form, [ 112,138,159,173,71,271–284 ] bottom‐up self‐assembly technology, [ 285–305 ] and emerging 3D printing technology. [ 306–317 ] Broadband absorption responses obtained by top‐down lithography can be further divided into the following categories, such as i) planar design method, [ 271–273 ] ii) vertical design method, [ 159,274–276 ] iii) adding active materials design method, [ 173,277–279 ] and iv) coding design method. [ 71,280–281 ] In describing self‐assembly technology for designing and manufacturing BMAs, we summarize previous works and divide them into two main aspects: the direct sputtering design approach, [ 285–293 ] and template assisted design method.…”

“…Due to its inherent lightness, affordability, and low space constraints, the design, and fabrication of BMAs using this technology have expanded considerably. [ 307–317 ]…”

“…For example, a flexible BMA optimized using a genetic algorithm and fabricated by 3D printing technology achieved an experimental reflectivity of −11.8 dB between 7 and 18 GHz. [ 317 ]…”

“…In this section, we focus on summarizing the design strategies of BMAs, mainly including three core strategies, such as top-down lithography form, [112,138,159,173,71,[271][272][273][274][275][276][277][278][279][280][281][282][283][284] bottom-up self-assembly technology, and emerging 3D printing technology. [306][307][308][309][310][311][312][313][314][315][316][317] Broadband absorption responses obtained by top-down lithography can be further divided into the following categories, such as i) planar design method, [271][272][273] ii) vertical design method, [159,[274][275][276] iii) adding active materials design method, [173,[277][278][279] and iv) coding design method. [71,[280][281] In describing self-assembly technology for designing a...…”

Design of wideband metamaterial absorber using circuit theory for X‐band applications

“…Recently, severalflexible absorbers were fabricated by 3D printing for microwave frequencies [53][54][55]. A flexible 3D printed absorber was fabricated based on rectangular conductive split ring resonator units by employing two different materials for two separate split ring resonators (Polylactic Acid (PLA) and Electrifi) [54].…”