Crystallization behavior and microstructural analysis of lead-rich (P b x S r 1 - X) TiO 3 glass ceramics containing 1mole L a 2 O 3

Abstract

Solid solution of perovskite Pb,SrTiO3 in Pb-rich composition can be crystallized in borosilicate glassy matrix. The addition of rare earth and transition metal oxides is known to influence the crystallization behavior and surface morphology of perovskite crystallites in glassy matrix. In the present paper, the glasses in the lead-rich system 64[(PbxSr1-x)TiO3]-25[2SiO2B2O3]- 5[K2O]-5[BaO] (1 ≤ x ≤ 0.5) with the addition of 1mol La2O3 were prepared to study its effect on their crystallization behavior. Differential thermal analysis (DTA) patterns show one or more exothermic crystallization sharp peaks, which shift towards higher temperature with increasing concentration of SrO. The glasses were subjected to various heat-treatment schedules for crystallization. X-ray diffraction analysis of these glass ceramic samples shows that major crystalline phase of the entire glass ceramic sample with x ≥ 0.5 was found to have tetragonal structure similar to PbTiO3 ceramic, and addition of La2O3 enhances the crystallization of the perovskite phase and retards the crystallization of minor phases.