Abstract:
In this paper, measurements of the nonlinear ferroelectric, piezoelectric and dielectric properties of Pb9Ce2Ti12O36 (Pb9CTO) and Ba2NdTi2Nb3O15 (BNTN) ferroelectric ceramics are presented. Hysteresis P(E) loops were measured as a function of applied electric field, frequency and temperature. The coercive field (E (c)) and remnant polarization (P (r)) displayed temperature and frequency dependence. Lead-free BNTN ceramics exhibited a coercive field E (c) > 2.4 kV mm(-1) and a piezoelectric coefficient d (33) = 2 pC N-1. The hysteresis loop was pinched above 110A degrees C and a linear response was observed at 155A degrees C, typical of a paraelectric material. Pb9CTO was shown to be ferroelectric with coercive field E (c) = 1.2 kV mm(-1) and a d (33) = 65 pC N-1. The frequency dependences of the impedance of the Pb9CTO discs were analyzed.
