Influence of the Sintering Conditions on the Microstructural, Dielectric and Piezoelectric Properties of La Doped KNNTa Ceramics

  • J. Portelles Facultad de Física, Universidad de La Habana & Universidad Nacional Autónoma de México, Centro de Nanociencias y Nanotecnología
  • J. Fuentes Facultad de Física, Universidad de La Habana & Universidad Nacional Autónoma de México, Centro de Nanociencias y Nanotecnología
  • O. Raymond Universidad Nacional Autónoma de México, Centro de Nanociencias y Nanotecnología
  • J. Heiras Universidad Nacional Autónoma de México, Centro de Nanociencias y Nanotecnología
  • M. Cruz Universidad Nacional Autónoma de México, Centro de Nanociencias y Nanotecnología
  • C. Ostos Universidad Nacional Autónoma de México, Centro de Nanociencias y Nanotecnología & Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México
  • G. G. C. Arizaga Universidad Nacional Autónoma de México, Centro de Nanociencias y Nanotecnología
  • J. M. Siqueiros Universidad Nacional Autónoma de México, Centro de Nanociencias y Nanotecnología

Abstract

Two batches of lead free ceramics of the composition (K0.5Na0.5)0.95La0.016Nb0.9Ta0.1O3 (KNNTaLa) were sintered between 1150 and 1180 °C. In the first batch, the samples were prepared in a sealed crucible embedded in powders of the same composition and, in the second, they were sintered in open air. Measurements made by X-ray diffraction, scanning electron microscopy and analysis of the phase transition and electromechanical response show, in general, a better performance for the encapsulated samples where very high values of density are obtained (about 97% of the theoretical density). La doping of KNNTa ceramics shifts its transition temperatures toward lower values, from 361 ºC to 317 ºC for the tetragonal-cubic (ferroelectricparaelectric) and from 187 °C to 150 °C for the orthorhombictetragonal (ferroelectric-ferroelectric) transitions in this particular composition. The obtained electromechanical parameters are reasonably good and show the potentiality of the KNNTaLa ceramic as a commercial piezoelectric material.

Published
Jul 15, 2014
How to Cite
PORTELLES, J. et al. Influence of the Sintering Conditions on the Microstructural, Dielectric and Piezoelectric Properties of La Doped KNNTa Ceramics. Revista Cubana de Física, [S.l.], v. 31, n. 1, p. 10-14, july 2014. ISSN 2224-7939. Available at: <https://revistacubanadefisica.org/index.php/rcf/article/view/RCF_31-01_10_2014>. Date accessed: 03 july 2022.
Section
Original Articles