Study of microstructure and thermal properties of PbTiO_3 based glass ceramics

摘要

Glass samples with composition (35- X) B_2O_3 - (40 +X) PbO - 25 TiO_2 (where = 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 (PbTiO_3) as a major crystalline phase and lead borate (PbB_2O_4) as minor crystalline phase. The microstructure of glass ceramic samples contains nano crystallites of lead titanate embedded in a borate glass matrix.