Wave absorbing performance of polymer-derived SiCN(Fe) ceramics

Ferreous polymer-derived SiCN ceramics (PDCs-SiCN(Fe)) were successfully synthesized by precursor conversion method. The phase composition and microstructure of the obtained products were investigated by XRD , SEM and TEM . The result indicated a mainly amorphous structure with a few α-Fe,and graphite phases in the gaps. The conductivity, electromagnetic parameters and wave absorbing properties of the prepared ceramics were studied at the frequency band from 2 to 18   GHz. The reflectance of PDCs-SiCN(Fe) was about −10   dB (> 90% absorption) in the range of 4–16   GHz with 25   wt% nano-Fe 2 O 3 addition at the thickness 8   mm. The maximum value of dielectric and magnetic loss angle tangent was about 1.5, indicating PDCs-SiCN(Fe) ceramics possessed good absorption performance .