Dielectric and microwave absorption properties of Ti₃SiC ₂ powders

Ti₃SiC₂ powders are synthesized via vacuum pressureless sintering method. The dielectric properties of the powders synthesized at different temperature are investigated in the frequency range from 8.2 to 12.4 GHz (X-band), which suggests the remnant TiC has obvious influence on complex permittivity and the pure Ti₃SiC₂ powders have the highest dielectric loss. The dielectric and microwave absorption properties of Ti₃SiC₂ powders are studied. Both the real part (ε′) and imaginary part (ε″) increase with Ti₃SiC₂ concentration but decrease with increasing frequency, which presents the obvious frequency dispersion effect. Furthermore, the effect of thickness on the microwave absorption property of Ti ₃SiC₂/paraffin mixture is analyzed. The mixture with 70 wt% Ti₃SiC₂ in 2.0 mm thickness presents the optimum microwave absorption property. The effective absorbing bandwidth (below -10 dB) is almost in the whole frequency range and the lowest reflection loss is -33.83 dB. The results show Ti₃SiC₂ powders are good microwave absorbents in the X-band frequency range.