Effects of Poling Process on KNN-Modified Piezoceramic Properties
January 28, 2010
Volume 93 Issue 2, Pages 318 – 321
F. Rubio-Marcos, Juan J. Romero, Diego A. Ochoa, Jose E. García, Rafael Perez, José F. Fernandez Published Online: Dec 3 2009 4:24PM DOI: 10.1111/j.1551-2916.2009.03404.x
The influence of the orthorhombic to tetragonal phase transition near room temperature in the poling process of KNN-modified piezoceramics was studied. Poling temperatures of 25° and 120°C were used. The percentage of 90° domains reorientation induced by poling was evaluated trough X-ray diffraction analysis. The improvement of the piezoelectric properties when the poling temperature was 25°C could not be explained by the reorientation of 90° domains alone. Raman spectroscopy evidenced that the polarization process was assisted by the stabilization of orthorhombic phase, which promotes a stress reduction in the material.