Investigation of Structural and Electrical Properties of Undoped and Fe-doped PNN-PZT Piezoceramics
YALÇIN E. 1, GÖZÜAÇIK N. 1, ALKOY S. 1, MENCUR E. 1
1 Gebze Technical University, Kocaeli, Turkey; 2 Gebze Technical University, Kocaeli, Turkey; 3 Gebze Technical University, Kocaeli, Turkey; 4 Gebze Technical University, Kocaeli, Turkey
Piezoelectric materials are used in underwater sonar systems, sensors and medical imaging. Lead zirconate titanate (PZT) is one of the commercially used ceramic with the highest piezoelectric/electromechanical properties in these applications. In the literature, various lead-based or lead-free ceramic compositions have been developed and studied to be used as an alternative to PZT. Lead nickel niobate-lead zirconate titanate (Pb(Ni1/3Nb2/3)O3-Pb(Zr0.3Ti0.7)O3) (xPNN-(1-x)PZT) is one of the relaxor ferroelectric composition which has been studied to reach the higher electrical properties.
In this study, 0.50PNN-0.50PZT and 0.55PNN-0.45PZT compositions were doped with 0.5, 1.0, and 1.5 mol% Fe, and the electrical and structural characterizations of the ceramics were carried out. All ceramic powders were fabricated by solid state reaction method. Disc-shaped ceramics were produced from the synthesized powders using a uniaxial press. The sintered ceramics were structurally characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrical characterization of all ceramics was carried out by measuring polarization-electric field (P-E) hysteresis, temperature-dependent dielectric constant and dielectric loss, and frequency-dependent admittance and phase angle. All measurement results were compared and discussed. The piezoelectric charge coefficient (d33) was measured as 705 pC/N and 590 pC/N for undoped 0.50PNN-0.50PZT and 0.5 mol% Fe doped 0.50PNN-0.50PZT, respectively.