Interfacial Reaction of BaTiO ₃ Ceramics with PbO–B ₂ O ₃ Glasses

Abstract

Interfacial reactions of pure, lead‐, and zirconium‐substituted BaTiO 3 ceramics with PbOB 2 O 3 glasses were studied, with an emphasis on the effect of glass composition. Microstructures were analyzed by scanning electron microscopy and electron‐probe microanalysis aided with X‐ray diffractometry of powder mixtures in the system BaTiO 3 PbOB 2 O 3 heated at 850°C. The interfacial microstructures were divided into two types, depending on the glass composition. The first type was characterized by precipitates of TiO 2 dispersed in the glass matrix. Extended heating or limited glass volume resulted in the formation of a continuous layer of BaTi(BO 3 ) 2 . The second type of microstructure was characterized by a lead‐rich perovskite phase, which developed at the glass/ceramic interfacial region. Growth kinetics for this phase denied the diffusion‐controlled mechanism. The substitution of lead in BaTiO 3 enhanced the penetration of glass into the ceramics along the grain boundaries and developed a coreshell structure.