Microstructural characteristics of (Pb 1− xCa x)TiO 3 materials

Abstract

Microstructural characteristics including ferroelectric domain boundaries, atomic ordering and TiO 6 octahedron tilting of Pb 1− x Ca x TiO 3 ( x=0.3, 0.4, 0.5) were studied and correlated to microwave properties. Using transmission electron microscopy, Pb 0.5Ca 0.5TiO 3 specimens reveal 1/2(1 0 0), 1/2(1 1 0) and 1/2(1 1 1) extra reflections regularly in electron diffraction patterns. Dark-field images show two different wavy boundaries using different extra reflections, and their contrast characteristics were discussed. High-resolution transmission electron microscopic (HRTEM) images exhibit ordering characteristics with 1/2(1 1 1) reflections. However, some regions showing no ordering characteristics also exhibit 1/2(1 0 0) and 1/2(1 1 0) reflections. An octahedron tilting model combined with atomic ordering was constructed to interpret diffraction behavior in Pb 1− x Ca x TiO 3 materials and the relation between microstructures and microwave properties was also discussed.