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Comparing the electromechanical properties of CaTiO3- and BaZrO3-modified Bi0.5Na0.5TiO3–SrTiO3 ceramics

Published online by Cambridge University Press:  07 October 2020

Hoang Thien Khoi Nguyen ,
Trang An Duong ,
Sang Sub Lee ,
Chang Won Ahn ,
Hyoung-Su Han Open the ORCID record for Hyoung-Su Han [Opens in a new window]  and
Jae-Shin Lee Open the ORCID record for Jae-Shin Lee [Opens in a new window]
Hoang Thien Khoi Nguyen
Affiliation:
School of Materials Science and Engineering, University of Ulsan, 12, Techno saneop-ro55 beon-gil, Nam-gu, Ulsan44776, Republic of Korea
Trang An Duong
Affiliation:
School of Materials Science and Engineering, University of Ulsan, 12, Techno saneop-ro55 beon-gil, Nam-gu, Ulsan44776, Republic of Korea
Sang Sub Lee
Affiliation:
School of Materials Science and Engineering, University of Ulsan, 12, Techno saneop-ro55 beon-gil, Nam-gu, Ulsan44776, Republic of Korea
Chang Won Ahn
Affiliation:
Department of Physics and EHSRC, University of Ulsan, 93, Daehak-ro, Nam-gu, Ulsan44610, Republic of Korea
Hyoung-Su Han
Affiliation:
School of Materials Science and Engineering, University of Ulsan, 12, Techno saneop-ro55 beon-gil, Nam-gu, Ulsan44776, Republic of Korea
Jae-Shin Lee*
Affiliation:
School of Materials Science and Engineering, University of Ulsan, 12, Techno saneop-ro55 beon-gil, Nam-gu, Ulsan44776, Republic of Korea
*
a)Address all correspondence to this author. email: [email protected]
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Abstract

The effects of CaTiO3 (CT) and BaZrO3 (BZ) modification upon the crystal structure and electromechanical properties of lead-free Bi0.5Na0.5TiO3–SrTiO3 piezoelectric ceramics were compared within a doping range of 0–4 mol%. The different effects of CT and BZ modification upon the phase transition are clearly observed in the polarization and strain hysteresis loops. The CT-modified specimens maintain strong ferroelectricity without any abnormal enhancement in the electric field-induced strain. However, the addition of as little as 1 mol% BZ induces a transition from a nonergodic relaxor phase to an ergodic relaxor phase, thus resulting in disruption of the ferroelectric order and the generation of a high field-induced strain. The present authors believe that the substitution of large ions (such as Zr4+) into the B-sites, rather than the A-sites, of the Bi0.5Na0.5TiO3-based ceramics plays a significant role in the phase transition behavior.

Keywords

ceramicpiezoelectricferroelectric
Type
Invited Feature Paper
Information
Journal of Materials Research , First View , pp. 1 - 10
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Copyright © The Author(s), 2020, published on behalf of Materials Research Society by Cambridge University Press

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