Broadband Electromagnetic Absorption in a Thermo-Oxidatively Stable SiOC Polymer Derived Ceramic Pyramidal Absorber...

Developing electromagnetic (EM) pyramidal absorbers that maintain stable, efficient, and broadband EM absorption in extreme high temperature environments is a critical yet challenging objective for advanced stealth technologies. Inspired by the anti-reflection structure of moth eyes, this work proposes complex pyramidal absorbers based on a multicomponent polymer derived ceramic composed of polydimethylsiloxane (PDMS), ZrB₂, and carbon black (CB), fabricated via direct ink writing (DIW) 3D printing. The results demonstrate that, through the synergy of conductive loss and interfacial polarization loss within the material, combined with the spatial gradient impedance matching effect, the absorbers achieve an exceptional reflection loss of -49.9 dB and an extremely wide effective absorption bandwidth (EAB) of 13.68 GHz. Furthermore, a radar cross section (RCS) reduction of 36.5 dBsm was achieved in far-field simulations. More importantly, the absorbers exhibit excellent service robustness, maintaining highly stable EM and mechanical properties under oxidative environments at 1000°C, while showing low sensitivity to wave polarization (TE and TM) and oblique incidence angles up to 45°. This work provides an effective strategy for the development of high temperature multifunctional stealth components for extreme environments.