Crystallization and microstructural behaviour of strontium titanate borosilicate glass ceramics with Bi2O3 addition

Glasses in the system (65-x) [SrO . TiO2]-(35) [2SiO(2) . B2O3]-(x) [Bi2O3] where x = 1, 5, 10 (wt%) prepared by melting in alumina crucible (1375-1575 K), were subjected to different heat treatment schedules followed by DTA studies. Crystallization study showed the formation of Sr2B2O5 as major phase at low temperature (approximate to 950 degrees C) heat treatment. At high temperatures, TiO2 and SrTiO3 with or without Sr2B2O5 crystallize out depending on heat treatment. In this paper, the influence of variation in composition, thermal treatment on the nature of crystallizing phases as well as on the resulting microstructures are investigated through XRD, IR and SEM. Uniform crystallization was achieved by suitable addition of Bi2O3 and proper heat treatment.