Preparation of [110] Grain Oriented Barium Titanate Ceramics by Templated Grain Growth Method and Their Piezoelectric Properties

Abstract

[110]-oriented barium titanate (BaTiO 3 ) ceramics were prepared by templated grain growth (TGG) method using [110]-oriented BaTiO 3 platelike particles as a template and hydrothermal BaTiO 3 sphere particles with different particle sizes as a matrix. The degree of orientation along the [110] direction, F 110 , was measured using an X-ray diffraction (XRD) pattern by the Lotgering method. To obtain both a high density and a high F 110 , the preparation conditions were optimized as functions of matrix particle size, volume fraction of the template to the matrix, and sintering temperature. As for the results, BaTiO 3 -grain-oriented ceramics with a high density of more than 96% were successfully prepared despite various F 110 values from 0 to 98%. Scanning electron microscopy (SEM) revealed that their average grain sizes were always approximately 75 µm despite various F 110 values and there were no anisotropic microstructures. These grain-oriented BaTiO 3 ceramics were poled at 100 °C, and their piezoelectric properties were measured using a resonance–antiresonance method and a piezo d 33 meter for d 31 and d 33 piezoelectric constants. As for the results, the d 31 values were almost constant at -50 pC/N despite various F 110 values, while the d 33 values increased with increasing F 110 values, and at around an F 110 of 85%, d 33 reached a maximum of 788 pC/N.