Growth of Single Crystals of BaTiO3 by Exaggerated Grain Growth

Grain-growth experiments with steep temperature gradients and with polycrystalline aggregates seeded with single crystals were carried out to explore the feasibility of growing large crystals of BaTiO₃ in the solid state. It is shown that both methods resulted in a large increase in size of crystals normally obtained by sintering but that the rapid grain-boundary motion resulted in high porosity. Definite orientation dependence of grain-boundary velocity is demonstrated, and growth in a 〈110〉 direction was found to be at least as fast as 2 mm per hour.