Abstract: The SiC@C nanoparticles were prepared under mixed gas（the partial pressure of H2，Ar and CH4 is 10 kPa，20 kPa and 7.5 kPa，respectively）by the direct ⁃ current arc method. The XRD and Raman spectrum were used to characterize the composition of SiC@C nanoparticles，and TEM was used to analyze their morphologies. The SiC@C nanoparticles were dispersed evenly in the paraffin matrix. The complex permittivity of the composite was measured at 100 MHz⁃18 GHz frequency range. It is found that the maximum reflection loss can reach ⁃27 dB when the microwave absorbing layer is 8 mm thick. Further analysis on the dielectric properties of SiC@C nanoparticles shows that the dipole relaxation comes from the（VC）vacancy and（VSi）vacancy in the SiC. The change of the electrical conductivity and relaxation process is the main influencing factor on the dielectric properties of the SiC@C samples.
DOI：10.14024/j.cnki.1004-244x.20161014.003