Premium
Optical and Microstructural Variations with Electric Field in Barium‐Strontium Titanate Ceramics
Author(s) -
SANVORDENKER VIOLA C.
Publication year - 1967
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1151-2916.1967.tb15100.x
Subject(s) - materials science , dielectric , ferroelectricity , ceramic , electric field , strontium barium niobate , barium titanate , strontium titanate , anisotropy , condensed matter physics , ferroelectric ceramics , permittivity , isotropy , mineralogy , optics , optoelectronics , composite material , chemistry , physics , quantum mechanics
Quasi‐thin sections of large‐grained ferroelectric barium‐strontium titanate ceramic compositions were observed under crossed polars. Dielectric constant and light transmission were measured as a function of temperature and applied dc voltages. Microscopic observations, such as changes in structure and in optical anisotropy with temperature and simultaneously applied electric fields, are described. Optical data indicate that static electric fields readily induce anisotropy in the isotropic grains at the ferroelectric to paraelectric transition of the ceramic. Below the transition temperature, the effect of the field on the optical and dielectric properties diminishes. Contrary to single‐crystal barium titanate, a field‐produced reorientation of domains in the ceramic at temperatures below the transition proceeds with difficulty, and is sometimes achieved only after long exposures to high‐biasing fields.