Ferroelectric glass-ceramics, with a basic composition (1Ày)(Ba 0.70 Sr 0.30 )TiO 3 -y(B 2 O 3 -x SiO 2 ), were synthesized by sol-gel method. The major crystalline phase is the perovskite, which exhibited volume nucleation. The formation of the crystalline phase, particle size, morphology, kinetics, and mechanism of crystallization of the ferroelectric in the glass matrix have been studied using differential thermal analysis, X-ray diffraction, and scanning electron microscopy. The kinetic parameters characterizing the crystallization of the perovskite phase have been determined using an Arrhenius model. The effect of glass content on the dielectric properties and the influence of the glass composition on the crystallization have also been investigated and are reported.

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Ferroelectric glass–ceramics with a basic composition (1 − y)(Ba0.70Sr0.30)TiO3 : y(BaO : Al2O3 : 2SiO2) have been synthesized by the sol–gel method. The major crystalline phase is the perovskite. The crystallization of the ferroelectric phase in the glass matrix have been studied using differential thermal analysis and x-ray diffraction and the kinetic parameters characterizing the crystallization have been determined using an Arrhenius model. Glass contents ≤ 5 mol% promoted liquid phase sintering, which reduced the sintering temperature to 1250 °C. The dielectric permittivity of the glass–ceramic samples decreased and the ferroelectric–paraelectric phase transition became more diffuse with increasing glass content. The dielectric connectivity of the ferroelectric phase in the composite have also been investigated and are reported.

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A simple inorganic system has been developed for the sol-gel synthesis of piezoelectric PZT-glass nanocomposites. Nanocrystalline PZT are nucleated from the amorphous xerogel through controlled heat treatment at 6001C. The formation of the crystalline phase, particle size, morphology, kinetics, and mechanism of crystallization of PZT in the glass matrix have been studied using X-ray diffraction, scanning electron microscopy, and differential thermal analysis. The piezoelectric characteristics of the PZT-glass compositions have been determined, and are correlated with the microstructure and the crystalline phase of PZT.

Ferroelectric glass-ceramics of composition 0.90 (Ba 0.7 Sr 0.3 ) TiO 3 -0.10(B 2 O 3 :SiO 2 ) (0.90 BST:0.10 BS) synthesized by sol-gel method have been used for the preparation of dielectric thick-film inks. The particle dispersion of the glass-ceramic powders in the thick-film ink formulations have been studied through rheological measurements for fabricating thick-film capacitors by screen printing technique. The thick films derived from such glass-ceramics are found to sinter at considerably lower temperatures than the pure ceramic, and exhibit good dielectric characteristics with a tunability of 32% at 1 MHz under a dc bias field of 35 kV/cm.

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