Comparative study of the polarization and strain of inclusion-type and layer-type 0.94Bi(NaK)TiO3–0.06BiAlO3/Bi(NaK)TiO3 ceramic composites

• Published in: Journal of alloys and compounds Vol. 646; pp. 1058 - 1067
• Main Authors: Jeong, Soon-Jong, Kim, Min-Soo, Jang, Seok-Myung, Kim, In-Sung, Mohsin, Saleem, Song, Jae-Sung
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.10.2015
• Subjects: Ceramic composites; Lead-free ceramics; Piezoelectrics; Polarization; Strain; Piezoelectrics; Polarization; Lead-free ceramics; Ceramic composites; Strain
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2015.06.031

This study presents a comparison between the inclusion-type and layer-type ceramic–ceramic composites, consisting of relaxor and piezoelectric phases, in terms of polarization and strain behaviors. Bi(NaK)TiO3 (BNKT) and 0.94Bi(NaK)TiO3–0.06BiAlO3 (BNKT–BA) were prepared for ferroelectric and relaxor materials, respectively. In the case of the layer-type composite, the polarization and strain behaviors were observed as a function of the volume ratio of the relaxor/piezoelectric phases. With an increase in the ratio of BNKT/BNKT–BA, a larger strain was obtained with the electric field. For the inclusion-type composite, the largest saturation polarization with double hysteresis loop and large saturation strain were measured at a ratio of 0.2. Comparison of the two composites indicates that larger polarization and strain were observed for the inclusion-type composite than the layer-type composite. This may be related to the fact that the ferroelectric phase serves as a preferential nucleation/growth site for the relaxor-to-ferroelectric phase transition in the relaxor matrix, which was evaluated using the polarization dynamics of the ferroelectric materials. [Display omitted] •We report the comparison between inclusion-type and layer-type composites.•Larger polarization and strain were observed for the inclusion-type composite.•The difference relies on the interfaces between the relaxor/ferroelectric phases.•The role of ferroelectric BNKT in relaxor/ferroelectric composite was discussed.