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In this paper, we are reporting structural, dielectric, ferroelectric and magnetic properties of polycrystalline composites (ferrite and ferroelectric) of PZT (PbZr0.55Ti0.45O3) + CNFO (Co0.8Ni0.2Fe2O4). The sample with composition x CNFO + (1-x) PZT (x = 0.00, 0.05, 0.10, 0.15 and 1.00) were prepared using the solid state double sintering method. Here the ratio x: (1-x) of two components is by weight. X-ray diffraction (XRD) studies show that lattice constant and tetragonality decreases with increasing ferrite content. Dielectric constant was found to decrease with increase in amount of CNFO. The value of tangent loss (tanδ) was reasonably low (< 0.04) for all the samples. Ferroelectric and ferrimagnetic behavior was confirmed by observing P-E and M-H hysteresis loop, respectively. The room temperature magnetoelectric coupling coefficient (α = dE/dH) was measured as a function of applied DC magnetic field. The value of α was observed to be maximum (855 μV/(cm.Oe)) at DC magnetic field of 1.7 kOe for sample with 5% CNFO. Value of piezoelectric coefficient ‘d33’ decreases from 133 to 60 pC/N. [ABSTRACT FROM PUBLISHER]

Magnetostrictive-piezoelectric (magnetoelectric) composites using magnetostrictive nickel zinc ferrite (NZF) and piezoelectric lead zirconate titanate (PZT) having compositional formula yNi0.8Zn0.2Fe2O4-(1-y)PbZr0.65Ti0.35O3(0 ≤ y ≤ 0.15 in the steps of 0.05) were synthesized by conventional solid state method. Room temperature P-E and M-H hysteresis loops were recorded to study ferroelectric and magnetic properties of composites respectively. Effect of electric poling on values of remanant magnetization (Mr) and saturation magnetization (Ms) was studied for all composite samples (y = 0.05, 0.10 and 0.15) to confirm magnetoelectric (ME) coupling. ME coefficient (dE/dH) was measured as a function of dc magnetic field for all composite samples. [ABSTRACT FROM PUBLISHER]

The composites consisting of Mn doped Ni0.8Zn0.2Fe2O4 and Zr substituted Ba0.9Sr0.10TiO3 (BST) where Zr varies from 0.00 to 0.16 in steps of 0.04 were prepared by conventional solid state reaction route. The existence of both phases was confirmed by the XRD patterns and the lattice parameters for each composition were calculated. The dielectric parameter such as dielectric constant and dielectric loss were measured as a function of frequency and temperature. As we increase the Zr in ferroelectric phase, the dielectric loss of composite samples decreases up to 1% from 8%, and also Tmax decreases towards room temperature. Observation of ferroelectric and magnetic hysteresis loops for all samples confirms the electric and magnetic nature of the samples. [ABSTRACT FROM AUTHOR]