Ultra-broadband and wide-angle absorption based on 3D-printed pyramid

This paper proposes a 3D-printed pyramidal absorber, which comprises of the printing filaments, carbon-loaded Acrylonitrile Butadiene Styrene (ABS). This ABS has certain absorption effects, and shows simple and rapid prototyping characteristics. Here, we experimentally demonstrated the directly printed pyramidal absorber showing the absorption more than 90% within the frequency range from 5.3 to 18 GHz. The incident energy at the low and high peak frequencies are mostly attenuated by lambda/4 resonances, corresponding to the wavelength of lambda/4 and 3 lambda/4 separately. Distinct from the flat absorber, the pyramidal structure and absorbent take synergistic effects for broadband absorption. Additionally, the pyramid maintained its absorption bandwidth within quite a wide incident angle, 50 degrees for transverse electric (TE) polarization and 60 degrees for transverse magnetic (TM) polarization. It is expected that the proposed pyramidal absorber has great potential for application in radar cross section reduction and electromagnetic shielding.