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Glass samples with composition (35- X) B2O3 − (40 +X) PbO - 25 TiO2 (where X = 0, 2.5, 5, 7.5 and 10 mol %) were prepared using conventional quenching technique. These glass samples were converted to glass ceramics by following two stage heat treatment schedules. The density (ρ) values of glass ceramic samples are higher than those of corresponding glass samples. It was observed that there was good correlation between the density and Coefficient of Thermal Expansion (CTE) results of the glass–ceramics. The XRD results in the glass ceramics revealed the formation of tetragonal lead titanate (PbTiO3) as a major crystalline phase and lead borate (PbB2O4) as minor crystalline phase. The microstructure of glass ceramic samples contains nano crystallites of lead titanate embedded in a borate glass matrix. [ABSTRACT FROM AUTHOR]

The composition of Anthracene and Lead Titanate is prepared using Solid State reaction method. Anthracene is a solid polycyclic aromatic hydrocarbon (PAH) of formula C14H10, consisting of three fused benzene rings. It is a component of coal tar. Lead (II) titanate is an inorganic compound with the chemical formula PbTiO3. It is the lead salt of titanic acid. Lead (II) Titanate is a yellow powder that is insoluble in water. At high temperatures, lead Titanate adopts a cubic perovskite structure. The samples of Anthracene Lead Titanate composites of suitable mixture ratio are prepared using Solid state reaction method. The Crystal structure of the calcined powders and also sintered ceramics were analyzed using XRD (X-ray diffraction). The microstructure of the sintered ceramics has been investigated by using SEM (Scanning Electron Microscopy).The dielectric constants were calculated for different mixture ratios and at different temperatures are reported in this paper. It was observed that an increase in temperature there is a change in the dielectric constants has also been reported in this paper. It observed that the dielectric constant increasing with temperature increases. [ABSTRACT FROM AUTHOR]

Currently, K0.5Na0.5NbO3 (KNN) based ceramics are the most promising family of lead-free piezoelectric. The composition [(K0.5−x/2 Na0.5−x/2Lix) NbO3 (x=0.01, 0.05, 0.07): LKNN] have been fabricated by standard solid-state reaction method. X-ray diffraction analysis of samples show composition dependent structural changes. The structure is found to be orthorhombic for x=0.01 and x=0.05. A morphotropic phase boundary between orthorhombic and tetragonal phases is found for x=0.07. LKNN ceramics with x=0.01 exhibits enhanced electro strains properties with dynamic d33* value of 418 pm/V, and a remnant polarization (Pr) of 12.6 µC/cm2. [ABSTRACT FROM AUTHOR]

Relaxation property is always matter of interest for the frequency dependent study of the ferroelectric materials. The Nyquist plot of the impedance data provides the information about the relaxation phenomena. Often, in solids, instead of a single relaxation time a distribution of the relaxation times is found, which arises from the different mechanisms. Usually, the relaxation times is varied by substitution and its influence is studied on the basis of the compositional effects, but the impact of the size of the substituent is rarely analyzed. Fundamentally, the substituted cations modulatethe crystal structure of the parent material, which attunes the relaxation phenomenon. In the current study, the Rb substituted lead free Na0.5Bi0.5TiO3 (perovskite structure, ABO3 type) is chosen as its A-site is compositionally disorder due to the presence of the different cations with dissimilar radii. The samples are prepared through the solid state sintering method. The imaginary part of the complex impedance (Z) vs its real part (Z) are plotted for all samples to verify the response of the grain and grain boundaries. At the higher temperatures (≥500°C) single semi-circular arcs are formed by the materials for all the compositions. Interestingly, two semi-circular arcs are observed for the material for the higher cation-site disordered system at lower temperature (below 300°C). The second circle is associated with the different relaxation time of the dipolar entity, which may be generated due to the substitution of the Rb1+. This observation prove that the cation size mismatch creates the variation in the relaxation times at the lower temperatures. The cation size mismatch also modulates the contribution of the grain boundary to the impedance property. The real part of impedance of the 4 mol %, substituted Na0.5Bi0.5TiO3 is enhanced than parent Na0.5Bi0.5TiO3, which fortifies its performance as a capacitor and energy storage device. [ABSTRACT FROM AUTHOR]

Glass samples with composition (35- X) B2O3 - (40 +X) PbO - 25 TiO2 (where X= 0, 2.5,5, 7.5 and 10 mol %) were prepared using conventional quenching technique. It was observed that as PbO content increases the values glass transition temperature (Tg) and crystallization temperature (Tc) decreases. The replacement of boron by a bigger Pb ion expands the network there by reducing the glass transition temperature (Tg). These glass samples were converted to glass ceramics by following two stage heat treatment schedule. The density(ρ) values of glass ceramic samples are higher than those of corresponding glass samples. It was observed that there was good correlation between the density and Coefficient of Thermal Expansion (CTE) results of the glass–ceramics. The XRD results in the glass ceramics revealed the formation of tetragonal lead titanate (PbTiO3) as a major crystalline phase and lead borate (PbB2O4) as minor crystalline phase. The microstructure of glass ceramic samples contains nano crystallites of lead titanate embedded in a borate glass matrix. As the content of glass former (B2O3) is reduced, the PbTiO3 crystals precipitated in glass matrix are observed to increase. The dielectric constant values of glass ceramic samples are higher than those of corresponding glass samples. [ABSTRACT FROM AUTHOR]

Glass samples with composition (50 - X) PbO - XCaO - 25 TiO2 - 25 B2O3 (where = 0, .5, 10 and 15 mol %) were prepared using conventional quenching technique. It was observed that with the addition of alkaline earth oxides to lead borate glass containing TiO2 alters the network (conversion of BO3 to BO4) increasing the rigidity of the glass which enhances the Tg. These glass samples were converted to glass ceramics by following two stage heat treatment schedule. The density values of glass ceramic samples are higher than those of corresponding glass samples. It was observed that there was good correlation between the density and CTE results of the glass-ceramics. The XRD results in the glass ceramics revealed the formation of tetragonal lead titanate as a major crystalline phase and Ca3Ti2O7 as minor crystalline phase. The ferroelectric nature of all the glass ceramic samples is confirmed by P - E hysteresis measurements. [ABSTRACT FROM AUTHOR]

Glass samples with composition (50 - X) PbO - (25 + X) TiO2 - 25 B2O3 (where X = 0, 5, 10 and 12.5 mol %) were prepared using conventional quenching technique. These glass samples were converted to glass ceramics by following two stage heat treatment schedule. The XRD results in the glass ceramics revealed the formation of tetragonal lead titanate as a major crystalline phase. The SEM results show rounded crystallite of lead titanate. The ferroelectric nature of all the glass ceramic samples is confirmed by P - E hysteresis measurements. The extended heat treatment of glass ceramic samples at 593K for 10 h exhibited saturated hysteresis loops with higher values of remnant polarization. [ABSTRACT FROM AUTHOR]