SiC nanofibers modified Si3N4 ceramics for improved electromagnetic interference shielding in X-band.

Home-made SiC nanofibers were introduced into Si 3 N 4 matrix for enhanced electromagnetic interference (EMI) shielding properties. The microstructural characterization revealed that SiC nanofibers modified Si 3 N 4 ceramic is composed of SiC conductive networks made of uniformly distributed SiC nanofibers, micro-pores and insulating Si 3 N 4 matrix. Moreover, EMI shielding effectiveness (SE T ) for SiC nanofibers modified Si 3 N 4 ceramic is dependent on SiC nanofibers content. When the SiC nanofibers content is increased from 0 to 8 wt%, the EMI SE T of as-prepared ceramics increased from 3.43–4.15 dB to 5.58–9.31 dB. Due to the low electrical conductivity of as-prepared ceramics, multi-reflection caused by the micro-pores and nanofibers networks is mainly responsible for the EMI shielding. The study indicates that introduction of SiC nanofibers would be a favorable solution for Si 3 N 4 based thermostructural material with an improved EMI shieding. [ABSTRACT FROM AUTHOR]