Nov 3, 2015 - the said properties was also studied. The maximum d33 and kp values for PLZT ceramics was found to be ~715 pC/N and ~77%, respectively.
Eur. Phys. J. B (2015) 88: 287
DOI: 10.1140/epjb/e2015-60414-9
Optimization of poling parameters of mechanically processed PLZT 8/60/40 ceramics based on dielectric and piezoelectric studies Ajeet Kumar, V.V. Bhanu Prasad, K.C. James Raju and A.R. James
Eur. Phys. J. B (2015) 88: 287 DOI: 10.1140/epjb/e2015-60414-9
THE EUROPEAN PHYSICAL JOURNAL B
Regular Article
Optimization of poling parameters of mechanically processed PLZT 8/60/40 ceramics based on dielectric and piezoelectric studies Ajeet Kumar1,2 , V.V. Bhanu Prasad1 , K.C. James Raju2 , and A.R. James1,a 1 2
Ceramics and Composites Group, Defence Metallurgical Research Laboratory, 500058 Hyderabad, India School of Physics, University of Hyderabad, 500046 Hyderabad, India Received 25 May 2015 / Received in final form 22 July 2015 c EDP Sciences, Societ` Published online 3 November 2015 – a Italiana di Fisica, Springer-Verlag 2015 Abstract. Ultra high strain (Pb0.92 La0.08 )(Zr0.60 Ti0.40 )O3 (PLZT 8/60/40) piezoelectric ceramics were synthesized by high energy ball milling method to study the relation between poling conditions (poling electric fields, times and temperatures) and electrical properties. The ceramics were structurally investigated and with the help of ferroelectric P -E hysteresis loop, coercive field was determined. This study deals with the identification of optimum poling conditions and their effect on the piezoelectric and dielectric properties mechanically synthesized PLZT 8/60/40 ceramics. Different combinations of poling parameters were used to measure the values of dielectric constant, dielectric loss, piezoelectric charge (d33 ) and electromechanical coupling coefficients (kp ). These values show that a ferroelectric material can be poled at ∼5 kV/cm (95%) [26], fine grain sizes, single and pure perovskite phase. Figure 1 shows the X-ray diffraction (XRD) pattern for the sintered compact of PLZT 8/60/40 ceramics. After sintering, pure perovskite single phase was observed for PLZT ceramics free from any secondary phases that indicate the complete chemical reaction. The density of the PLZT 8/60/40 ceramics were calculated using Archimedes’s principle and found to be >98% relative of the theoretical density. Grain size is an important factor that affects the dielectric constant along with tetragonality (c/a ratio), phase transition temperature (Tc ) and polarization of the ferroelectric ceramics. Fractured surface of the sintered PLZT 8/60/40 ceramics show a very dense microstructure, uniform grain sizes with clearly visible grain shapes indicating the existence of a polycrystalline microstructure with average grain size
