Enhanced electromagnetic wave absorption performance of multiphase (TiC/TiO2/C)/SiOC composites with unique microstructures

Abstract

Incorporating multiphases can not only increase the attenuation capacity but also partially alleviate impedance mismatch. In this work, (TiC/TiO2/C)/SiOC composites were prepared from polymer-derived ceramics (PDCs) using a TiC nanoparticle modified polysiloxane (PSO) precursor at 900 °C under an Ar flow. The addition of TiC serves a dual purpose of enhancing conductivity loss and acting as a source of Ti for the generation of TiO2 particles. The combination of these particles with the carbon layer in amorphous SiOC creates a multiphase loss medium that significantly improves not only conductive loss and dipole polarization loss but also interface polarization loss, resulting in excellent impedance matching characteristics and EM wave absorption. Accordingly, the (TiC/TiO2/C)/SiOC with a TiC fraction of 20 wt% indicated a significant minimum reflection loss (RLmin) of −54.2 dB (over 99.999% absorption), and the effective absorption bandwidth (EAB) covered 4.2 GHz with a thickness ranging from 2.5 to 3.3 mm in the X band. A maximum radar cross section (RCS) reduction of 24.6 dBm2 was achieved at a scattering angle of 75°. Thus, the (TiC/TiO2/C)/SiOC composites have the potential to be utilized in radar stealth technology and reduce EM pollution, offering a novel approach to address these challenges.