Enhanced electromagnetic microwave absorption of SiOC ceramics targeting the integration of structure and function

The electromagnetic waves (EMW) absorption properties of SiOC ceramics synthesized by polymer-derived method were investigated, and additive manufacturing was employed to obtain the integration of structure and functions. The presence of free carbon and beta-SiC nanocrystallites increased the internal relaxation interfacial polarization, which improved the EMW absorption properties significantly. In particular for the sample pyrolyzed at 1200 degrees C, the effective absorption bandwidth (EAB, RL<-10 dB) and minimum reflection loss (RL)were 4.9 GHz (at a thickness of 1.58 mm) and -23.5 dB, respectively, indicating the excellent EMW absorption properties of this SiOC material. In addition, we 3D printed two typical porous structures (a log-pile grid and a gyroid) in which the thickness of solid element corresponded to the one providing optimal absorption. Additive Manufacturing of designed structures will enable to improve and further optimize the selection and control of the absorbing material in practical applications.

Automated summary

SiOC ceramics synthesized by the polymer-derived method exhibit excellent EMW absorption properties, with the presence of free carbon and beta-SiC nanocrystallites significantly enhancing their absorption characteristics. 3D printing technology can be used to create structures with optimal absorption performance, aiding in the improvement and optimization of absorbing material selection in practical applications.