Vector impedance characterization of the structural changes in lead zirconate titanate ceramics doped with manganese

Abstract

Vector impedance measurements of radial mode and its three overtones of Pb (Zr,,,3Ti,,,,)0, (PZT) disk doped with MnO in the range of X = 0.1 to 9.2 mole% have been carried out using a computer controlled impedance analyzer at the room temperature. An effective value of the Poisson's ratio (8) has been determined from the fundamental to overtones frequencies ratio which comes out to be 0.34 S 0.01. The planar coupling coefficient K, is found to be independent of the overtones and peaks at around X = 1.0 mole% whereas the dielectric constant KT, peaks at X = 0.46. The coupling coefficient K , , , elastic compliance sf,, strain constant d,, and voltage constant g3, have been determined and found to be independent of overtones. The exponent 'p' and constant 'A' of the ac conductivity -frequency power law (~( u c ) = A,fP) are 0.92 and 8.7 pS/m for X < 1.0 which jumps to 0.75 and 73.8 pS/m at X 2 1.0. The values of 'p' are less than 1, which suggests that hopping mechanism is responsible for the conduction in PZT ceramics. Large variation in the piezoelectric and dielectric parameters around X = 1.0 are due to the structural changes.

Dielectric and piezoelectric properties of neodymium oxide doped lead zirconate titanate ceramics

“…The lead zirconate titanate [Pb(Zr, Ti)O 3 ] ceramics, to which oxides such as La 2 O 3 , Nb 2 O 5 , Fe 2 O 3 , NiO, MnO 2 , IrO 2 , ThO 2 , WO 3 , Cr 2 O 3 and U 3 O 8 have been added and studied by several workers (Jaffe et al 1971;Thomann 1972;Troccaz et al 1978;Wu et al 1982;Heywang and Thomann 1984;Moulson and Herbert 1990;Katiyar et al 1994Katiyar et al , 1997 due to their wide application in various piezoelectric, ultrasonics and underwater devices along with various actuators and sensors in different fields of science and technology. The effect of addition of rare earth oxides in Pb(Zr, Ti)O 3 ceramics have mostly been related with the incorporation of La +3 ions into Pb(Zr, Ti)O 3 ceramics which increases their dielectric constant, electromechanical parameters and dielectric loss and decreases mechanical quality factor.…”

Dielectric, ferroelectric and piezoelectric studies of neodymium-modified PLZNT ceramics for sensor and actuator applications

“…The 3 have exhibited a significant impact in the dielectric and piezoelectric properties in PLZNT ceramic system. X-ray diffraction patterns indicated that doped compositions exhibited FE TET with increasing Nd content.…”

“…piezoelectric properties. Another mechanism could be due to the presence of donor ions in the perovskite with the increasing Nd content contribute considerably to the piezoelectric effect [3]. The addition of neodymium causes significant changes on electromechanical properties which can be seen in Fig.…”

“…due to their wide application in various piezoelectric, ultrasonic, underwater devices, and various sensors and actuators [1][2][3]. The morphotrophic phase boundary (MPB) which separates the two different regions, viz.…”

Temperature dependence of electromechanical properties of PLZT x/57/43 ceramics

“…C a decreases with the overtones also. C a , in the piezoelectric equivalent circuit, represents the elastic compliance 11 E s and the charge constant d 31 , transformed into its electrical equivalent by the piezoelectric effect (Mason 1964;Jaffe et al 1971;Katiyar et al 1997).…”