Oriented growth of piezoelectric crystallites at the normal direction of glass cylinders

摘要

The oriented crystallites were found to grow from the cylindrical surface toward inside at the normal direction during the crystallization in the BaO–SrO–TiO₂–SiO₂ glass. The oriented growth in the cylinders was consistent with the heat transfer direction in the post-thermal treatment, in which the temperature was rapidly increased from the transition point of the glass to the point for the bulk crystallization in a precisely temperature-controlled furnace. The crystalline phase, (Ba_0.2Sr_1.8)TiSi₂O₈, was evenly embedded in the glass phase in the non-ferroelectric piezoelectric glass ceramics. The cylinders with oriented crystallization can be machined into the piezoelectric tubes with radial polarization.