Electromechanical Properties of Some Pb (Mg_1/3Nb_2/3–PbTiO₃–(Ba,Sr)TiO₃ Ceramics: I

Abstract

Compositional variation within the Pb(MgInNb2,3)03-PbTi03 -(Ba,Sr)Ti03 (hereafter PMN-PT-BT,ST) ternary (6.4% 5 PT% 5 14.1%, 1.25% 5 BT,ST% 5 2.5%) results in major changes in induced strain and hysteresis. For the 1.25% BT family, the increase in strain correlates with an increase in Tma,, while the dielectric loss is uncorrelated with hysteresis and strain. In addition, weakfield aging (which is not reset by application of field) shows little effect on strain and hysteresis for drive fields of > 0.2 MV/m. The vary narrow polarization-field loops (virgin curves nearly indistinguishable from subsequent cycles) show that weak-field permittivity is a good approximation to the high-field permittivity. Although these data clarify the frequency (T,,,,, is linearly dependent on the logarithm of the frequency) effect on weak-field dielectric behavior, they do not directly address the question of meaningful extrapolation of high-field strain with frequency. In particular, the question remains as to whether the high-field permittivity and strain are frequency dependent. In future papers we will address this question by a combination of measurement techniques as functions of frequency. [Key words: lead magnesium niobate, electromechanical properties, dielectric properties, aging, strain.]

Structural and electrical properties of (1−x)(Na1/2Bi1/2)TiO3–xPb(Mg1/3Nb2/3)O3 solid solution

“…Above the room temperature, PMN has a very slim polarization and strain vs. electric field (P2E) curve with a small coercive field. In addition, the dielectric loss of PMN decreases rapidly above the room temperature [8,9]. Therefore, it is expected that addition of PMN compensate the shortcomings of NBT; high coercive field and high conductivity.…”

ielectric Studies of Cd-Substituted PMN Relaxor

“…It is well known that in relaxor ferroelectrics the frequency dependence of T m cannot be described by simple Arrhenius law which is to be expected for Debye relaxation process. Recent studies [8,12,[18][19][20] showed that, like in spin and structural glass, this dependence obeys the empirical Vogel-Fulcher law [21,22]:…”

“…The ferro-paraelectric phase transition (T m ) and all the related properties in these systems are characterized not by abrupt changes, but rather by gradual diffuse changes, which occur over a wide temperature range [3,4]. Among the various electrostrictive materials, Pb(Mg 1/3 Nb 2/3 )O 3 (PMN)-based materials have carried special attention because of their better dielectric and electrostrictive properties [5][6][7][8][9][10]. The dielectric relaxation in PMN-based materials has been investigated extensively, and believed that it is similar to the magnetic relaxation in spin-glass system.…”

Application of Fourier harmonic analysis to the electromechanical response of an electroactive material

“…The samples used were originally fabricated during the late 1980's and early 1990's. 20,21 The (1 Ϫx)Pb(Mg 1/3 Nb 2/3 )O 3 -xPbTiO 3 materials doped with BaTiO 3 or SrTiO 3 compositions ͑PMN-PT-BT, ST͒ are contained in a ternary, as shown in Fig. 1.…”

“…22 were used here to allow direct comparison͒. 24 The technique developed here demonstrates how Fourier harmonic analysis of the electromechanical signal of an electroactive material can be related to the underlying physics of the response. This provides the necessary relationship to obtain the strain coefficients ͑function of applied electric field͒ of the material.…”