Fabrication of 〈110〉 grain-oriented 0.15BaTiO₃–0.85(Bi_0.5Na_0.5)TiO₃ceramics by a reactive templated grain growth method

Abstract

〈110〉 grain-oriented ceramics with the composition of 0.15BaTiO3–0.85(Bi0.5Na0.5)TiO3 with a high Curie temperature of ∼300 °C were successfully fabricated by reactive templated grain growth of layered hydrogen titanate platelets with (Bi0.5Na0.5)TiO3 and BaCO3 matrix powders. A large degree of 〈110〉 orientation F110 = 84% was achieved by decreasing green sheet thickness and application of pressure on a compact during sintering. As a consequence, improved remanent polarization was observed in these ceramics compared with randomly oriented ceramics, owing to easier polarization switching. A piezoelectric constant d33 of 103 pC/N and an electromechanical coupling factor k33 of 0.44 were obtained for the 〈110〉 grain-oriented ceramics.

Preparing 0.15BaTiO₃–0.85(Bi_0.5Na_0.5)TiO₃ ceramics using spark plasma sintering

“…Moreover, the ceramics that presented large GS also featured large d 33 values. Nevertheless, the d 33 values of the ceramics in this study were very low compared with those reported by Ueno et al 9) Their ceramics exhibited high degree of orientation, which could have been the most probable reason for their high d 33 values. However, the relative density decreased.…”

“…The XRD patterns of the ceramics obtained using SPS presented the single BTBNT phase. Because the XRD patterns of BTBNT 9) were almost same as our obtained results. However, the peaks in the XRD pattern of the ceramics obtained using CV sintering separated at approximately 40°, which suggested the presence of mixed phase BT and BNT in the structure of these ceramics.…”

“…In addition, the composition of 0.15BNT 0.85BT contributed to its higher T c . 8) Grain oriented 0.15BT0.85BNT ceramics with the d 33 value of 103 pC/N, which were obtained utilizing the reactive templated growth method using plate-like H 1.08 Ti 1.73 O 4 •nH 2 O (HTO, Konoshima Chemical) were reported by Ueno et al 9) In this study, the properties of 0.15BT0.85BNT ceramics obtained using SPS, have been analyzed.…”

Optimization of preparation conditions of highly textured piezoelectric (Bi_0.5K_0.5)TiO₃ ceramics

“…Sintering with weight-pressing could control the warpage associated with the oriented grains. 36) The warpage observed in the ceramics was controlled by pressing the debinded samples which was wrapped in platinum foil during sintering (WS). A crucible containing zirconia balls was used to impose a pressure of 17 kPa.…”

“…32) With using the HTO template particles, ©110ª-oriented platelike BaTiO 3 particles, ©110ª-oriented 0.15BaTiO 3 0.85(Bi 0.5 Na 0.5 )TiO 3 ceramics, and ©100ª-oriented (Bi 0.5 Na 0.5 )TiO 3 ceramics have been successfully fabricated recently. 32),34), 36) In this study, we optimized various preparation conditions and successfully fabricated singleperovskite phase and highly textured BKT ceramics using HTO template particles by the RTGG method via a conventional sintering method.…”