Fabrication of (111)-oriented Tetragonal BaTiO₃ Ceramics by an Electrophoretic Deposition in a High Magnetic Field

Abstract

(111)-oriented tetragonal barium titante (BaTiO 3 , BT) ceramics with the degree of (111) orientation of 100 % were fabricated by sintering (001)-oriented hexagonal BT accumulations prepared by a magnetic field assisted electrophoretic deposition (EPD) method. Apparent piezoelectric constant d 33 * value calculated from the slope of a unipolar strain vs. electric field curve of the (111)-oriented tetragonal BT ceramics was 597 pm/V, which was larger than that of randomly oriented ceramics (d 33 * = 460 pm/V). This enhancement was associated with an electric field induced phase transition.

Fabrication of 〈110〉 grain-oriented 0.15BaTiO3–0.85(Bi0.5Na0.5)TiO3ceramics by a reactive templated grain growth method

“…A grain orientation technique is effective for improving piezoelectric properties in anisotropic ferroelectric materials. [1][2][3][4][5][6] For example, off-polar 〈110〉 grain-oriented barium titanate (BT; BaTiO 3 ) ceramics exhibited a larger piezoelectric constant d 33 of 788 pC=N 7) than randomly oriented ceramics with the d 33 of 191 pC=N, 8) and the increased d 33 was comparable to that of lead zirconate titanate (PZT) ceramics with a similar Curie temperature. 9) Barium titanate-bismuth sodium titanate [BT-BNT; Ba-TiO 3 -(Bi 0.5 Na 0.5 )TiO 3 ] solid solutions are among the promising lead-free piezoelectric materials.…”

Phase evolution and <110>‐orientation mechanism in RTGG‐processed BaTiO3 ceramics with electrical properties

“…With <110> grain orientation in BaTiO 3 ceramics, the piezoelectric coefficient increased significantly (788 pC/N) 9 than that of its randomly oriented counterpart (191 pC/N) 10 . Various grain‐orientation techniques have been reported for enhancing piezoelectric properties in various ferroelectric materials, 11‐15 among which a reactive templated grain growth (RTGG) method is the widely used process in perovskite‐structured ferroelectric materials. The RTGG method has been reported to be well‐suited for fabricating grain‐oriented BaTiO 3 16 and BaTiO 3 ‐based ceramics 5,7,17‐19 …”

Preparation and investigation of hexagonal-tetragonal BaTiO₃ powders

“…8) Regarding the enhancement of piezoelectric coefficient of the BT ceramics, Kobayashi et al took ©111ªdirection of its engineered domain configurations with the hope that one extra equivalent domain along this direction will help for additional enhancement in the piezoelectric coefficient. 9) For this, they adopted a high-magnetic-field electrophoretic deposition (HM-EPD) method with a hexagonal BT powder which has a larger lattice constant c/a ratio than a tetragonal BT powder to facilitate the magnetic alignment of the particle. Although ©111ª-oriented BT ceramics were prepared, their piezoelectric properties were not enhanced.…”