Microwave Absorbing Properties Of MgCuZnFe2O4 + PZT Nanocomposites For EMI Applications

Abstract

Microwave absorbing properties of MgCuZnFe2O4 + PbZrTiO3 nanocomposites were studied in the x band region of microwave frequencies. Mg0.48Cu0.12Zn0.4Fe2O4 and Pb(Zr0.52Ti0.48) O3 nanopowders were prepared using high energy mechanical milling method. The milled powders were characterized by Fourier Transform Infrared Spectrometer (FTIR), X-Ray diffractometer (XRD) and Scanning Electron Microscope (SEM). A series of xPb(Zr0.52Ti0.48) O3 + (1-x) Mg0.48Cu0.12Zn0.4Fe2O4 (x =0-1) nanocomposites were prepared by high energy mechanical milling and sintering method. The perovskite phase (PZT) and spinel phase (MCZ) of composites were confirmed by XRD and SEM. The average grain size of the composites was in the range 120-162 nm. The magnetic and ferroelectric properties of the composites were investigated from the studies of magnetic and ferroelectric hysteresis. The complex permeability and permittivity of the present composites were measured in the x band frequency range of 8-12 GHz using a vector network analyzer. The reflection loss and shielding effectiveness of the composites were calculated from the measurements of complex permeability and permittivity. The minimum reflection loss is found to be less than -25 dB with band width greater than 0.4 GHz, for all the nanocomposite samples, which implies 99% of power attenuation of electromagnetic wave. The microwave absorption increases with the increase of ferrite phase in the nanocomposite. The composite with 20 mol% (x=0.2) ferroelectric phase has shown a minimum reflection loss of -34.3 dB near 10.45 GHz with bandwidth of 0.71GHz. From these studies, the prepared nanocomposite samples are considered as good microwave absorbing materials for electromagnetic interference applications and hence can be designed to act as microwave shields. Copyright © 2016 VBRI Press