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This paper explores the templated grain growth and texturing of Pb(Yb1/2Nb1/2)O3‐Pb(Mg1/3Nb2/3)O3‐PbTiO3 (PYN‐PMN‐PT) ceramics. A PbO‐CuO liquid phase was determined to substantially increase the growth of PYN‐PMN‐PT on barium titanate template particles. Texturing resulted in an 83% enhancement in strain behavior (754 pm/V) compared with random PYN‐PMN‐PT ceramics (413 pm/V). The increased Pb(Yb1/2Nb1/2)O3 (PYN) content of textured 21PYN‐41PMN‐38PT resulted in a high coercive field of 13.9 kV/cm. Residual barium titanate templates reduced the polarization from 33.7 to 26.2 µC/cm2 and slightly decreased the Curie temperature (236‐224°C). These results show that textured PYN‐PMN‐PT is a promising material for high strain and coercive field transducers. [ABSTRACT FROM AUTHOR]

This study explores sintering and piezoelectricity of ZnO‐doped perovskite Pb(In1/2Nb1/2)O3‐Pb(Zn1/3Nb2/3)O3‐PbTiO3 (PIN‐PZN‐PT) ceramics. The enhanced densification of ZnO‐doped PIN‐PZN‐PT is attributed to the formation of oxygen vacancies by the incorporation of Zn2+ into the perovskite B‐site and increased rate of bulk diffusion relative to undoped PIN‐PZN‐PT. Incorporation of Zn2+ into the perovskite lattice increased the tetragonal character of PIN‐PZN‐PT as demonstrated by tetragonal peak splitting and increased Curie temperature. Sintering in flowing oxygen reduced the solubility of Zn2+ in the perovskite lattice and resulted in rhombohedral PIN‐PZN‐PT. Sintering in oxygen prevented secondary phase formation which resulted in a high‐piezoelectric coefficient (d33 – 550 pC/N), high‐coercive field (Ec – 13 kV/cm), and high‐rhombohedral to tetragonal phase transition temperature (Tr‐t – 165°C). We conclude that ZnO‐doped PIN‐PZN‐PT ceramics are excellent candidates for high‐power transducer applications. [ABSTRACT FROM AUTHOR]

The quality of crystallographic alignment in textured ceramics produced by tape casting and templated grain growth (TGG) has been little studied despite its demonstrated impact on magnetic, piezoelectric, and optical properties. Physical and crystallographic alignment of anisotropic template particles is shown to be directly linked to the casting rate, gap height, and casting viscosity during tape casting. These parameters are shown to affect the shape and magnitude of the shear rate profile under the doctor blade during casting which in turn causes a gradient in the torque acting on anisotropic particles. The magnitude of the torque, the time the slurry is exposed to torque during casting, and the ratio of casting height to template diameter are demonstrated to enable the particle alignment process to be tailored to produce well‐aligned template particles. Crystallographic alignment of the textured ceramic was quantified by grain misalignment angle (full width at half maximum, FWHM) and degree of orientation (r) and is directly correlated with the degree of torque during casting. High‐quality alignment (FWHM = 4.5°; r = 0.13) was demonstrated in the model TGG system consisting of submicrometer alumina and 5 vol% 11 μm diameter template platelet particles. [ABSTRACT FROM AUTHOR]