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(1-x)Mg0.7Zn0.3Fe2O4-(x)Ba0.7Sr0.3TiO3 ceramics composite with x = 0.0, 0.2, 0.4, 0.6 and 1.0 were prepared by the solid state reaction method. The spinel structure of the ferrite phase and perovskite structure of ferroelectric phase were confirmed by x-ray diffraction (XRD). SEM micrographs reveal compatibility of ferrite grains with ferroelectric grains. It can be seen size of grain decrease with increase Ba0.7Sr0.3TiO3 phase concentrations. The magnetic property can be identified from the magnetic permeability of the sample and the values were observed to be 0.53–0.83 N/A2 and its increases with the increasing of Mg0.7Zn0.3Fe2O4 phase contents. The electrical resistivity values were found to be in the range ∼0.06–52.99 MΩm. The dielectric constant was determined as a function of frequency (in the range 100–104 Hz). The results also reveal that for the lower concentrations of Mg0.7Zn0.3Fe2O4, ferroelectric behavior is noticed with a high electrical resistivity and dielectric constant.

Phase formation dependence of microstructure and mechanical properties were studied in 0.65Al2O3–0.35ZrO2 with 2 to 8 wt.% Y2O3 addition (AZY). Phase composition of the samples were characterized by x-ray diffraction (XRD) technique. It was found that the major phase was the rhombohedral-Al2O3, while the minor phase consisted of the monoclinic (m)-ZrO2, tetragonal (t)-rO2, cubic (c)-ZrO2 and monoclinic (m)- Y2O3. It has been found that the optimal contents of Y2O3 prohibited growth of grain in ceramics and obtained highly dense ceramics. It was found that the smaller grains had high fracture toughness. The maximum fracture toughness of 4.204 MPa m1/2 was obtained from 8 wt% Y2O3. Refinement of lattice parameters using Rietveld analysis revealed that the quantitative phases of AZY ceramics. This shows that under Y2O3 addition conditions the proportion of tetragonal-ZrO2 phase play an important role for the mechanical properties of AZY ceramics.

Mg 0.7 Zn 0.3 Fe 2 O 4 (MZF) ceramics were fabricated using solid state reaction route. Phase formation, microstructure, electrical, magnetics and mechanical properties were studies. It has been fo...

Perovskite powder of (1-x)Pb(Mg 1/3 N 2/3 ) O 3 –xPbTiO 3 ;(1-x)PMN-x PT at x between 0.20-0.40, this region of morphotopic phase boundary (MPB) of the PMN-PT system, have been prepared by a solid-state reaction via a Ball-milling technique. Phase formation of the samples powder has been investigated as a function of different compositions of x by XRD technique. It can be found that a continuous series of perovskite solid solution in the (1-x)PMN-x PT system was formed and indicated the MPB region at x value about 0.32 and this area has coexistent with two ferroelectric phases (rhombohedral and tetragonal). With increasing PT concentration in the range of x = 0.32–0.40, tetragonality factors tend to increased (∼ 1.001–1.002). Moreover, morphology and particle size evolution have been determined via SEM technique. The average particle size range by SEM is between 0.125–0.875 μ m. Average size of particle between 0.039 and 0.047 μ m was calculated by Scherer's equation from XRD patterns.

Mg0.7Zn0.3Fe2O4 (MZF) powder was prepared by a solid-state mixed oxide using ball-milling technique. The phase identification of calcined powders was performed using X-ray diffraction technique (XRD). It has been found that MZF powders were successfully obtained for calcination conditions of 800 oC for milling times of 36 h, whereas milling times of 12 h, unreacted ZnO, Fe2O3 and MgO phases (2θ ~ 54, 57 and 63) are detected from the original mixture up to 900 oC. By increasing the calcination temperature to 1000 oC, a single phase of MZF is formed. Moreover, the microstructure of powder were examined by scanning electron microscopy (SEM) and showed that the particle in size from 58-1200 nm. While, XRD patterns were obtained average size of particle, calculation by Scherrer's equation, between 30.54 - 66.59 nm.