Determination of the electrocalorinc properties of the ferroelectric (1-x)BaTiO3-Bi(Li1/3Ti2/3 (O≤x≤0.2) system
tarafından
 
Demirtay, Tuğçe, author.

Başlık
Determination of the electrocalorinc properties of the ferroelectric (1-x)BaTiO3-Bi(Li1/3Ti2/3 (O≤x≤0.2) system

Yazar
Demirtay, Tuğçe, author.

Yazar Ek Girişi
Demirtay, Tuğçe, author.

Fiziksel Tanımlama
xiii, 87 leaves: illustrarions, charts;+ 1 computer laser optical disc.

Özet
The aim of this study is to develop electrocaloric (EC) materials for alternative eco-friendly cooling technologies. Considering the dielectric and piezoelectric properties of the (1-x)BaTiO3- xBi(Li1/3Ti2/3)O3 (0≤x≤0.2), this system was selected to study electrocaloric properties due to the presence of morphotropic phase boundary (MBP). The crystal structure of the samples that were synthesized by convential solid state reaction technique were determined by the X-Ray Diffraction experiments. The electrical properties of the ceramics were characterized by temperature-dependent dielectric measurements and the phase transition temperatures of the samples were identified. Temperature-dependent electrical polarization curves were measured for all compositions and electrocaloric temperature change values were calculated with the help of Maxwell equations. Using the dielectric measurements, a phase diagram was obtained. Strain-electric field measurements were done to complement dielectric and polarization measurements. A new antiferroelectric phase was discovered at high temperatures in the samples. As Bi(Li1/3Ti2/3)O3 content is increased, phase transition from the ferroelectric to antiferroelectric phase decreases. Since in the antiferroelectric phase the net polarization is very small, a large polarization change therefore large electrocaloric temperature change is obtained. Highest electrocaloric temperature change (ΔT=0.66 K under 22 kV/cm) is obtained for x=0.03 sample.

Konu Başlığı
Ferromagnetic materials.
 
Ferroelectric crystals.
 
Ferroelectric devices.

Yazar Ek Girişi
Adem, Umut

Tüzel Kişi Ek Girişi
İzmir Institute of Technology. Materials Science and Engineering.

Tek Biçim Eser Adı
Thesis (Master)--İzmir Institute of Technology: Materials Science and Engineering.
 
İzmir Institute of Technology: Materials Science and Engineering--Thesis (Master).

Elektronik Erişim
Access to Electronic Versiyon.


LibraryMateryal TürüDemirbaş NumarasıYer NumarasıDurumu/İade Tarihi
IYTE LibraryTezT001890QD931 .D37 2018Tez Koleksiyonu