Thermal depolarization and electromechanical hardening in Zn2+‐doped Na1/2Bi1/2TiO3‐BaTiO3.

Na1/2Bi1/2TiO3‐based materials have been earmarked for one of the first large‐volume applications of lead‐free piezoceramics in high‐power ultrasonics. Zn2+‐doping is demonstrated as a viable route to enhance the thermal depolarization temperature and electromechanically harden (1‐y)Na1/2Bi1/2TiO3‐yBaTiO3 (NBT100yBT) with a maximum achievable operating temperature of 150 °C and mechanical quality factor of 627 for 1 mole % Zn2+‐doped NBT6BT. Although quenching from sintering temperatures has been recently touted to enhance TF‐R, with quenching the doped compositions featuring an additional increase in TF‐R by 17 °C, it exhibits negligible effect on the electromechanical properties. The effect is rationalized considering the missing influence on conductivity and therefore, negligible changes in the defect chemistry upon quenching. High‐resolution diffraction indicates that Zn2+‐doped samples favor the tetragonal phase with enhanced lattice distortion, further corroborated by 23Na Nuclear Magnetic Resonance investigations. [ABSTRACT FROM AUTHOR]
Copyright of Journal of the American Ceramic Society is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)