In:
Journal of the American Ceramic Society, Wiley, Vol. 97, No. 2 ( 2014-02), p. 507-512
Abstract:
The dielectric and ferroelectric characteristics of ( Sr x Ba 1− x ) Nb 2 O 6 unfilled tungsten bronze ceramics have been investigated together with the structure. The dielectric and ferroelectric characteristics of the present ceramics vary significantly with x , and the A1/A2‐sites occupancy has been determined as the primary parameter governing this variation tendency. Ba ions tend to occupy A2‐sites, Sr ions tend to occupy A1‐sites, and one A1‐site is empty. When the ratio of Sr / Ba is close to 1:4 (where four A2‐sites are just occupied by Ba ions, and one A1‐site is occupied by Sr ion while another A1‐site is empty), the normal ferroelectric transition is observed with one anomaly in the tanδ– T curve ( x = 0.25). When the ratio of Sr / Ba is far away from 1:4, the typical relaxor behavior is indicated together with three anomalies in the tanδ– T curve ( x = 0.75). The incommensurate oxygen octahedral tilting and A‐site random distribution are considered to be the structure origins for the relaxor ferroelectricity and low temperature dielectric relaxations.
Type of Medium:
Online Resource
ISSN:
0002-7820
,
1551-2916
DOI:
10.1111/jace.2014.97.issue-2
Language:
English
Publisher:
Wiley
Publication Date:
2014
detail.hit.zdb_id:
2008170-4
detail.hit.zdb_id:
219232-9
Permalink