2021年第68回応用物理学会春季学術講演会

講演情報

一般セッション(口頭講演)

9 応用物性 » 9.1 誘電材料・誘電体

[18p-Z16-1~16] 9.1 誘電材料・誘電体

2021年3月18日(木) 13:30 〜 18:00 Z16 (Z16)

塚田 真也(島根大)、上野 慎太郎(山梨大)、森本 貴明(防衛大)

16:00 〜 16:15

[18p-Z16-10] Influence of grain size effect and Ba/Ti ratios on dielectric, ferroelectric, and piezoelectric properties of Barium titanate ceramics

〇(D)Piyush Sapkota1、Ichiro Fujii1、Shintaro Ueno1、Satoshi Wada1 (1.Univ. of Yamanashi)

キーワード:Dielectric

The grain-size effect on the dielectric, ferroelectric, and piezoelectric properties of BaTiO3 (BT) ceramics with different Ba/Ti ratios, prepared by solid-state reaction and conventional sintering, was investigated, and the corresponding electrical properties of these ceramics with similar grain size were compared. The BT ceramics with Ba/Ti ratios of 0.997, 1.000, and 1.003 and grain sizes of approximately 1 µm exhibited dielectric constants of 4265, 4275, and 4835 and converse piezoelectric coefficients, d33*, of 703, 645, and 466 pm/V, respectively. The remanent polarization, Pr, was relatively higher for Ba-excess BT ceramics, as shown in Fig. 1. These results indicated that, in Ti-excess BT ceramics, domain walls were strongly pinned due to oxygen vacancies under small electric fields and they were de-pinned at high electric fields, contributing to the higher d33*, while the orientation of domains in high electric fields would not retain upon electric-field unloading, resulting in lower Pr.