Bio-Inspired Microwave Modulator for High-Temperature Electromagnetic Protection, Infrared Stealth and Operating Temperature Monitoring

Abstract

High-temperature electromagnetic (EM) protection materials integrated of multiple EM protection mechanisms and functions are regarded as desirable candidates for solving EM interference over a wide temperature range. In this work, a novel microwave modulator is fabricated by introducing carbonyl iron particles (CIP)/resin into channels of carbonized wood (C-wood). Innovatively, the spaced arrangement of two microwave absorbents not only achieves a synergistic enhancement of magnetic and dielectric losses, but also breaks the translational invariance of EM characteristics in the horizontal direction to obtain multiple phase discontinuities in the frequency range of 8.2–18.0 GHz achieving modulation of reflected wave radiation direction. Accordingly, CIP/C-wood microwave modulator demonstrates the maximum effective bandwidth of 5.2 GHz and the maximum EM protection efficiency over 97% with a thickness of only 1.5 mm in the temperature range 298–673 K. Besides, CIP/C-wood microwave modulator shows stable and low thermal conductivities, as well as monotonic electrical conductivity-temperature characteristics, therefore it can also achieve thermal infrared stealth and working temperature monitoring in wide temperature ranges. This work provides an inspiration for the design of high-temperature EM protection materials with multiple EM protection mechanisms and functions.

Achieving Ultra-Wideband and Elevated Temperature Electromagnetic Wave Absorption via Constructing Lightweight Porous Rigid Structure

“…First of all, such ultra-wideband absorbing performance is readily achieved at room temperature. Nevertheless, considering the various applicabilities toward a high-temperature (up to 473 K) or harsh environment, absorbing frequency band usually requires to cover a specified region such as but not limited to full band coverage in military X-band [35][36][37]. Secondly, the porous structure of aerogel is soft and compressible to some extent that is a lack of ability to withstand certain compression.…”

Morphology-Controlled Fabrication Strategy of Hollow Mesoporous Carbon Spheres@f-Fe2O3 for Microwave Absorption and Infrared Stealth

“…4,5 Consequently, developing stealth materials with highperformance microwave absorption (MA) and low thermal infrared emission from the perspective of component-structure microdesign is a productive technical approach to achieve radar−infrared compatible stealth. 6,7 Metal oxide semiconductors have broad application prospects in multiband compatible stealth for avoiding the oxidation of magnetic components in the air and the overlapping problems of conductive materials. 8 α-Fe 2 O 3 is a high-temperature-resistant N-type semiconductor component with considerable dielectric loss capability and frequencyinsensitive dielectric parameters (ε′ and ε″), which contribute to the impedance matching at high frequencies.…”

“…With the rapid development of detection systems and the improvement of detection accuracy, the demand for advanced stealth technology is rising. Therefore, it is of great significance to develop new compatible stealth materials that can meet the stealth requirements of both GHz microwave stealth and infrared. − However, a tough problem still remains in achieving the balance of different types of stealth modes since microwave stealth requires reduced reflection and enhanced absorption performance of electromagnetic waves (EMW), whereas infrared stealth demands low-infrared emissivity and good temperature control property (Figure a). , Consequently, developing stealth materials with high-performance microwave absorption (MA) and low thermal infrared emission from the perspective of component-structure microdesign is a productive technical approach to achieve radar–infrared compatible stealth. , …”

Microstructure Design of High-Entropy Alloys Through a Multistage Mechanical Alloying Strategy for Temperature-Stable Megahertz Electromagnetic Absorption

“…Facing longer wavelengths than gigahertz EMW, absorbers demand larger and more matched complex permittivity and complex permeability to achieve broadband EMW absorption in the MHz band [ 12 – 16 ]. In addition, the harsh service environments bring challenges to the multi-temperature adaptability (at − 50–150 °C) and corrosion resistance of EMW absorbers [ 13 , 17 – 22 ]. Excellent permeability and its temperature stability are of a paramount significance for achieving broadband and temperature-stable EMW absorption in the MHz frequency range [ 13 , 23 ].…”