IMF2017

Crystallographic texturing of polycrystalline piezoelectric ceramics offers a convenient means of achieving significant enhancement in the electromechanical properties. Textured ceramics are usually prepared by template grain growth (TGG) or reactive template grain growth (RTGG) utilizing preferred orientation seed crystal. The synthesis mechanism confirmed that the texture process is driven by the difference in the surface free energies between the template crystal plane and the matrix grains. A series of results reported by our group suggested that texture engineering was an efficient means of enhancing piezoelectric performance not only in BNT-based system but also in KNN- and BCZT-based materials. In the case of <001>-textured BNT-BKT ceramics, a high field-induced strain coefficient of 710 pm/V was obtained under a relatively low driving field of 45 kV/cm. Furthermore, the <001>-textured KNN-based ceramics exhibited a 60%-70% improvement in the longitudinal piezoelectric coefficient as compared to its randomly oriented counterpart. Improvement in piezoresponse by the texture process can be attributed to the intrinsic anisotropy of crystallography and the domain switching difference.