INTEMA   05428
INSTITUTO DE INVESTIGACIONES EN CIENCIA Y TECNOLOGIA DE MATERIALES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Synthesis and characterization of K0.5Na0.5NbO3-BaTiO3-based lead-free piezoelectric ceramics
Autor/es:
M. CASTRO; A. PRADO; L. RAMAJO; RUBIO-MARCOS, FERNANDO
Lugar:
Foz- Iguazu
Reunión:
Congreso; 7th International Congress on Ceramics; 2018
Institución organizadora:
University of São Paulo (Polytechnic School)
Resumen:
Lead-based ceramics are widely used piezoelectric materialsdue to their excellent piezoelectric properties, but they are not environmentallyfriendly due to lead oxide toxicity. [1] Therefore, a number of studies have beencarried out to improve electrical properties of different kind of ABO3perovskites. [2] In the (1-x)K0.5Na0.5NbO3-xBaTiO3system the effect of (K,Na) substitution by Ba decreases the temperature of themaximum dielectric permittivity and improves the dielectric properties. Consequently,this kind of materials can be used as an alternative candidate to replace conventional piezoelectric materials [3].In this work, we present the synthesis and characterization of (1-x)K0.5Na0.5NbO3?xBaTiO3,(x= 0.03, 0.04, 0.05, 0.06, 0.07) based lead-freepiezoelectric ceramics through the solid-state reaction route. Powders weremixed in different compositions with the final propose of obtaining extensiveapplications. Itwas observed that Ba2+ ions occupy the A sites of the perovskitestructure, while Ti4+ ions replace Nb5+ ions at the B sites,resulting in the distortion of the perovskite structure. Additionally, for the highest BaTiO3concentration a practically constant dielectric constant curve was registeredfrom 20 to 500°C, whereas the loss tangent values ​​were low.