Journal article

Textured BaTiO3 by templated grain growth and electrophoretic deposition

[001]-Oriented barium titanate (BaTiO3) ceramics were prepared by templated grain growth using [001]-oriented plate-like template BaTiO3 particles, synthesized via the molten salt method. Platelets synthesized in a 2-step or 3-step molten salt were used in two platelet concentrations. The platelets were aligned in the green body via electrophoretic deposition. The use of different templates and concentrations played an important role in the alignment, the grain growth, and the properties of the ceramics. The highest degree of texture was observed in the ceramic textured with 1 wt% platelets made by the 3-step molten salt method. The addition of template particles limited the discontinuous grain growth and reduced the grain size. Texture enhanced the dielectric and piezoelectric properties of BaTiO3 ceramics, but the bismuth contamination associated with platelet addition was responsible for a high conductivity. The Curie temperature (T (C)) was 2-4 A degrees C higher in the textured ceramics than in the randomly oriented equivalents (130 A degrees C). The d (33) values increased with increasing crystal orientation and reached a maximum of 274 pC/N for the BaTiO3 textured with 1 wt% platelets made by the 2-step molten salt method, versus the d (33) of 186 pC/N for the randomly oriented.


Related material