High thermal stability of piezoelectric properties in (Na0.5Bi0.5TiO3)(x)-(BaTiO3)(y)-(Na0.5K0.5NbO3)(1-x-y) ceramics

We report the piezoelectric and ferroelectric properties of (Na0.5Bi0.5TiO3)(x)-(BaTiO3)(y)-(Na0.5K0.5NbO3)(1-x-y) ceramics for Na0.5K0.5NbO3 rich end of composition (x, y <= 0.04 mol. %). These compositions were found to exhibit significantly improved thermal stability of piezoresponse. Variation of dielectric constant as a function of temperature revealed that orthorhombic-tetragonal (To-t) and tetragonal-cubic (T-c) transition temperatures for these compositions were in the vicinity of 0 degrees C and 330 degrees C, respectively. Dynamic scaling and temperature dependent X-ray diffraction analysis were conducted. Results are discussed in terms of intrinsic and extrinsic contributions to the piezoelectric response explaining the temperature dependent behavior. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4773983]