Study of PbO-SrO-TiO2-B2O3 glass and glass ceramics

The glasses with composition (50−X)PbO-XSrO-25TiO2-25B2O3 (where X=0, 5, 10 and 15 mol%) were prepared using conventional quenching technique. The Tg, Tc, density and CTE of the glass samples were measured. The Tg observed to increase with increasing concentration of SrO, while the Tc first decreased and then increased. The 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 measurements. The XRD results revealed the formation of ferroelectric lead titanate as a major crystalline phase in glass ceramics. Additional phases observed include Sr2B2O5 and PbB2O4. The room temperature (RT) dielectric constant of glass and glass ceramics are in the range of 100-120 which is promising for capacitor application.