Effect of Ti₃SiC₂ addition on microwave absorption property of Ti₃SiC₂/cordierite coatings

Ti₃SiC₂/cordierite (MAS) composite coatings with different Ti₃SiC₂ concentrations were prepared via atmosphere plasma spraying (APS) method. The characteristics of the Ti₃SiC₂/MAS powders and as-sprayed coatings, such as microstructure, and phase constitution, were observed and measured. The effect of the Ti₃SiC₂ addition on the electromagnetic shielding, dielectric, and microwave absorption properties of Ti₃SiC₂/MAS coatings in the frequency of 8.2-12.4GHz was measured and discussed. The addition of Ti₃SiC₂ can significantly improve the electromagnetic shielding and complex permittivity of the coatings, which can be ascribed to the enhanced polarization effect and electrical conductivity. When the Ti₃SiC₂ content increases to 30wt.%, the coating shows an excellent microwave absorption property, and the effective absorption bandwidth (≤-5dB) can be obtained across the whole measured frequency with a thickness of 1.8mm. Further increase in Ti₃SiC₂ content led to high permittivity, which is harmful to the impedance match and results in strong reflection and weak absorption.