Polar Directions of the 90° and 180° Ferroelectric Domains in Tetragonal Barium Titanate Determined by Electron‐Backscatter Diffraction

Abstract

Ferroelectric domains induced in pressureless‐sintered BaTiO 3 ceramics by the cubic to tetragonal phase transformation at Curie point T C ≈130°C have been analyzed using electron‐backscatter diffraction (EBSD) equipped with the scanning electron microscope. The EBSD technique with built‐in automatic indexing algorithms enabling the differentiation of the {110} family, and the measurement of the twin obliquity has permitted unambiguous assignment of the fourfold c ‐axis and twofold a ‐axes from Kikuchi patterns obtained from the twin domains. Both the 90° and 180° domains with mutually perpendicular and parallel polar directions thus determined are consistent with those deduced by the traditional techniques whereby the polar directions were resolved morphologically from the configuration of domains, and from differential etching rate along the a ‐ and c ‐axis of the tetragonal phase. The successful demonstration of domain identification using EBSD has confirmed that the traditional techniques relying on differential etching rate are suitable for the purpose.