Abstract
Magnetoelectric composites containing Ni0.7Zn0.3Fe2O4 and Pb0.93La0.07(Zr0.60Ti0.40)O3 phases
have been prepared by chemical co-precipitation method. The structure and morphology of
the composites were examined by means of X-ray diffraction (XRD) and scanning electron
microscopic (SEM) The XRD result showed that the composites consisted of spinel
Ni0.7Zn0.3Fe2O4 and perovskite PLZT annealing at temperature higher than 700 oC. The
average grain size for the piezoelectric phase of the composite was found to increase the
overall dielectric and ferroelectric properties of the composite increased with increasing in
sintering temperature. Variation of dielectric constant (ε) and dielectric loss (tanδ) with
frequency for 0.30NZFO + 0.70PLZT composite with annealed at different temperature
showed dispersion in the low frequency range. The variation of dielectric constant with
temperature reflects DPT type behaviour. The dielectric properties are strongly influenced by
interface phenomena (Maxwell-Wagner) due to the local electrical inhomgeneity. At low
frequency range, the composite showed the dielectric dispersion is associated with very high
polarization. The peak value of dielectric constant for composite decreased with increasing its
sintering temperature. coercivity, saturation magnetization and squareeness have been found
to vary with concentration of ferrite phase and annealing temperature due to the increase in
crystallite size. The maximum value of the magnetoelectric conversion factor (dE/dH)max
equal to 5.2 mV/cm.Oe is observed for 30%NZFO – 70% PLZT composites when sintered at
1100 oC.
have been prepared by chemical co-precipitation method. The structure and morphology of
the composites were examined by means of X-ray diffraction (XRD) and scanning electron
microscopic (SEM) The XRD result showed that the composites consisted of spinel
Ni0.7Zn0.3Fe2O4 and perovskite PLZT annealing at temperature higher than 700 oC. The
average grain size for the piezoelectric phase of the composite was found to increase the
overall dielectric and ferroelectric properties of the composite increased with increasing in
sintering temperature. Variation of dielectric constant (ε) and dielectric loss (tanδ) with
frequency for 0.30NZFO + 0.70PLZT composite with annealed at different temperature
showed dispersion in the low frequency range. The variation of dielectric constant with
temperature reflects DPT type behaviour. The dielectric properties are strongly influenced by
interface phenomena (Maxwell-Wagner) due to the local electrical inhomgeneity. At low
frequency range, the composite showed the dielectric dispersion is associated with very high
polarization. The peak value of dielectric constant for composite decreased with increasing its
sintering temperature. coercivity, saturation magnetization and squareeness have been found
to vary with concentration of ferrite phase and annealing temperature due to the increase in
crystallite size. The maximum value of the magnetoelectric conversion factor (dE/dH)max
equal to 5.2 mV/cm.Oe is observed for 30%NZFO – 70% PLZT composites when sintered at
1100 oC.