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The effect of pressure of pelletisation on the density, microstructure, dielectric, ferroelectric, piezoelectric and energy storage density of B-site Zr doped barium titanate has been studied. X-ray diffraction confirmed that zirconium form complete solid solution with barium titanate. It has been observed that 4 ton/cm2 is an optimum pressure of pelletisation which gives maximum density, maximum dielectric constant, maximum piezoelectric constant and high energy storage density with efficiency of 67.68%. There is a good correlation among the density, grain size, dielectric, ferroelectric and piezoelectric properties. These results suggest that this material has a potential for energy storage applications. [ABSTRACT FROM AUTHOR]

LiNbO3has been synthesized by solid state sintering technique. The glass 30Li2O: 50B2O3: 10 Nb2O5: 10SiO2has been synthesized by conventional quenching technique. Different weight percentage of glass was added into LiNbO3ceramics and sintered at different temperatures. The samples were characterized by using X-Ray Diffraction, Density and Scanning Electron Microscope. The dielectric and ferroelectric measurements of these ceramics suggests that the addition of glass has helped in improving its properties. The LiNbO3ceramic with 5 wt% glass addition has shown optimum properties among the ceramics prepared. [ABSTRACT FROM AUTHOR]

PbTiO3glass-ceramics were prepared by following two stage heat treatment schedule. The effect of heat treatment duration on the physical properties of glass-ceramic was studied. The density, CTE, dielectric constant and ferroelectric properties varied systematically with heat treatment duration and exhibited an optimum for 32 h. These properties have a good correlation with the volume fraction of lead titanate phase crystallized in the glass-ceramics. Impedance spectroscopy was used to analyse the behaviour of glass-ceramic samples. The studies of ferroelectric properties show that PbTiO3glass-ceramics has a potential for high temperature applications. [ABSTRACT FROM PUBLISHER]

Glasses of compositions (50 -X) PbO-X CaO-25 TiO2-25 B2O3 (where X = 0,5,10 and 15 mol%) were prepared by conventional quenching technique. The glass samples were converted to glass ceramics by two stage heat treatment schedule. The XRD results confirmed the formation of ferroelectric PbTiO3 as a major phase in the glass ceramics. For all the CaO added samples the dielectric constant as a function of temperature, exhibit a peak around 475°C, which is close to the Curie temperature of PbTiO3. The hysteresis measurement supports the ferroelectric nature of the glass ceramics. [ABSTRACT FROM PUBLISHER]

Glass samples with composition of (50-X) PbO-X BaO-25 TiO2-25B2O3 (where X = 0, 5, 10 and 15 mol%) were prepared using conventional quenching technique. The amorphous nature of glass samples were confirmed by XRD. The glass transition temperature, Tg and crystallization temperature Tc were determined from the DTA. It has been observed that the addition of BaO enhances the Tg and reduces the Tc. These glass samples were converted to glass ceramics by following two stage heat treatment schedule. The glass ceramic samples were characterized by XRD, SEM and dielectric constant measurements. The dielectric constant for all the glass ceramic samples was observed to be higher than that of corresponding glass samples. Further, with addition of BaO the dielectric constant for glass ceramic samples increases up to 10 mol% of BaO and beyond this concentration it decreases. The XRD results revealed the formation of ferroelectric Lead Titanate as a major crystalline phase in the glass ceramics. This is supported by the SEM results which show rounded crystallites of lead titanate. This explains the enhancement in the dielectric constant. The addition of BaO to the glass contributes to the formation of BaB2O4 and Barium-Titanium-Borate (BTB) phases. Additional phases observed in these glasses include PbB2O4 and PbB2O7. This has been supported by SEM results indicating needle-like crystals in glass ceramic samples containing higher concentration of BaO. The observed hysteresis (P vs. E) loop at room temperature confirmed the ferroelectric nature of these glass ceramics. [ABSTRACT FROM AUTHOR]

The lead titanate based glass samples were prepared by conventional quenching technique. The Tg, Tc and density of the glass samples were measured. The glass samples were converted to glass ceramics by two stage heat treatment schedule. The dielectric constant has been studied for the glass and glass ceramics. The glass ceramic sample obtained by optimized heat treatment schedule exhibited maximum density and dielectric constant due to precipitation of crystalline PbTiO3 phase. [ABSTRACT FROM AUTHOR]