Electromagnetic properties of ferroelectric/ferromagnetic composite materials base on low temperature cofired ceramic technology

Abstract

The Ni-Cu-Zn ferrite(NCZF)/ BaTi O3 (BT) composite materials with mass ratio of BT/NCZF (x) =10%, 20%, 30%, and 40% were synthesized by usual ceramic technology and sintered at 900 °C to adapt to the low temperature cofired ceramic technology. The sintered density of the composite with x=40% is 5.454 g cm3 which is higher than that of the Ni-Cu-Zn ferrite (5.349 g cm3). The composites with x=10% and 20% have stable values of ε′ and lower values of tan δ. The ε′ of the composite with x=40% decreased from 256 to 39 when the frequency increased from 1 MHz to 1 GHz. The microstructures of the sintered ceramics were observed and analyzed by scanning electron microscopy. The permeability spectra of the composites with different BT contents had been resolved into contributions of domain wall resonance and spin rotation relaxation. The fitting results of permeability dispersion revealed the relationships among the above two mechanisms and microstructures. The influences of different composition on the electromagnetic properties of the composites were investigated. © 2009 American Institute of Physics.