The 69th JSAP Spring Meeting 2022

Presentation information

Oral presentation

9 Applied Materials Science » 9.1 Dielectrics, ferroelectrics

[26a-E307-1~9] 9.1 Dielectrics, ferroelectrics

Sat. Mar 26, 2022 9:00 AM - 11:30 AM E307 (E307)

Hajime Nagata(Tokyo Univ. of Sci.), Takaaki Morimoto(National Defence Academy)

11:00 AM - 11:15 AM

[26a-E307-8] Electrical and Electromechanical Properties of Bi4-xLnxTi3O12 Ceramics

〇Hiroshi Maiwa1 (1.Shonan Inst. Tech.)

Keywords:Ferroelectrics, Bi4Ti3O12, Lead-free

Bi4Ti3O12 (BIT) ceramics and Bi3.25Ln0.75Ti3O12 ceramics (Ln = La or Nd, BLT and BNT) ceramics were prepared by solid state reaction. The crystal structure, microstructure, and the dielectric and electromechanical properties are investigated. Substitution of Bi with La or Nd deteriorates sinterability, and the optimum sintering temperatures are higher than that of BIT. The firing temperatures of BIT, BLT, and BNT shown below are 1000 ℃, 1100 ℃ and 1150 ℃, respectively. In each case, the crystal grains grew as the sintering temperature increased. Most samples showed c-axis orientation in which flat particles spread. Figures 1 and 2 show polarization – electric field (P-E) loops and strain – electric field (s-E) loops of BIT, BLT and BNT, respectively. BNT has a large remanent polarization value, but also has a large coercive field (Ec). BLT shows the largest strain value among them. Since BNT has a large Ec, the maximum strain was not so large under the applied electric field. The results of piezoelectric properties will also be reported.