Publication Date
2-6-2019
Department
Ames Laboratory; Materials Science and Engineering
Campus Units
Materials Science and Engineering, Ames Laboratory
OSTI ID+
1494936
Report Number
IS-J 9879
DOI
10.1103/PhysRevMaterials.3.024402
Journal Title
Physical Review Materials
Volume Number
3
Issue Number
2
First Page
024402
Abstract
(Bi 1/2Na 1/2)TiO 3-based solid solutions, one of the major systems of lead-free piezoelectric ceramics, exhibit a low thermal depolarization temperature ( T d~100°C). It was reported that by incorporating 30 mol% ZnO particles to form a ceramic composite of (Bi 1/2Na 1/2) 0.94Ba 0.06TiO 3/ZnO, the depolarization process can be shifted up to ~250 °C. In the present work, a variety of advanced transmission electron microscopy techniques, including in situ heating, annular bright-field, high-angle annular dark-field, geometric phase analysis, energy-dispersive spectrum and electron energy-loss spectroscopy, are employed to investigate the underlying mechanisms for the enhanced thermal stability of polarization in the composite. Furthermore, it is found that the abrupt depolarization in (Bi 1/2Na 1/2) 0.94Ba 0.06TiO 3 at T d becomes diffused over a wide temperature window up to the temperature at maximum dielectric constant ( T m) under the combined actions of the incorporation of Zn into the perovskite lattice, the presence of residual stresses, and the pinning effect on micron-sized domains provided by ZnO particles.
DOE Contract Number(s)
DMR-1465254; AC02-07CH11358; 11674156
Language
en
Department of Energy Subject Categories
36 MATERIALS SCIENCE
Publisher
Iowa State University Digital Repository, Ames IA (United States)
