Dielectric properties and magnetoelectric effect of (x)NiFe2O4 plus (1-x)Ba0.8Sr0.2TiO3 composites

Magnetoelectric composites of NiFe2O4 and Ba0.8Sr0.2TiO3 were prepared using conventional double-sintering ceramic method. The phase formation of magnetoelectric composites was confirmed by XRD technique. Variation of dielectric constant and loss tangent at room temperature with frequency in the range 100 Hz-1 MHz has been studied. Also the variation of dielectric constant and loss tangent with temperature and composition at fixed frequencies of I kHz, 10 kHz, 100 kHz and I MHz is reported. The static value of the magnetoelectric conversion factor was measured as a function of intensity of the magnetic field. The ME voltage coefficient of about 430 mu V/cm Oe was observed for 15% NiFe2O4 + 85% Ba0.8Sr0.2TiO3 composite. All the samples show linear variation of magnetociectric conversion in the presence of static magnetic field. (C) 2007 Published by Elsevier Ltd.