Kinetics of Compositional Ordering in Pb2B′B″O6 Crystals

Abstract

The process of isothermal compositional ordering in the Pb2ScNbO6 ferroelectric and Pb2InNbO6 antiferroelectric is studied. Variation in the degree of the compositional long‐range order is brought about by annealing at high temperature and the subsequent quenching and is registered by its effect on dielectric characteristics in the Curie point region. The compositional ordering in oxides studied appeared to proceed most probably via non‐nucleation mechanism. In crystals with non‐homogeneous defect distribution and in ceramics a macroscopically non‐homogeneous process of ordering is observed. A model of the ordering kinetics in ceramics is proposed.

Ferroelectric properties of Pb(Zr1/2Ti1/2)O3–Pb(Zn1/3Nb2/3)O3 ceramics under compressive stress

“…However, the trend for E c is reversed. These observations are anticipated because the ceramic systems gradually change from the compositions with tetragonal structure (x = 0.1 and 0.2) with high E c and low P r to the near MPB compositions with the highest polarization values, and finally to the compositions with rhombohedral structure (x = 0.4 and 0.5) with low E c and high P r , as mentioned in previous investigation [14][15][16][17]. This clearly clarifies the existence of the MPB near x = 0.3 and 0.4, as reported earlier [21].…”

“…This amount of the energy loss is directly related to the amount of domain participating in the switching process during the application of electric field [10]. Unlike in the PMN-PZT system, in which the stress-free loop area decreases with increasing PMN content, as the ceramics gradually change from ferroelectric PZT with macro-domain states to electrostrictive PMN with nano-domain states [13,17], the stress-free loop areas of all the ceramics are generally very similar. For a given composition, the decrease in the loop area with increasing the compressive stress is a result of the stressinduced domain wall suppression [10].…”

“…PZN is a ferroelectric material with frequency dependent dielectric relaxation behavior, as well as diffuse phase transition at 140°C [17]. A single crystal of PZN shows extremely high dielectric and piezoelectric constants [18].…”

X-ray and electron diffraction studies of the structures of pseudo-perovskite compounds Pb2(Sc,Ta)O6 and Pb2(Mg,W)O6

“…Pbz(Fe,Nb)O6 (Brixel, Rivera & Schmid, 1984) and those in which the B-site cations can attain varying degrees of LRO, e.g. PST (Setter & Cross, 1980a;Bokov, Raevskii, Smotrakov & Prokopalo, 1986;Stenger & Burgraaf, 1980) and PMW (Zaslavskii & Bryzhina, 1963). The degree of LRO in PST has been known to influence the relaxor properties and thus the temperature at which the PE to FE transition takes place (Setter & Cross, 1980b;Bokov, Raevskii & Smotrakov, 1983;Smolenskii, 1970;Cross, 1987).…”

Synthesis, formation and characterization of lead indium niobate–lead titanate powders

“…Lead indium niobate Pb(In 1/2 Nb 1/2 )O 3 (PIN) compounds are interesting for studying the kinetics of compositional ordering [1]. It has been reported that the degrees of ordering on the B-site can be varied by thermal annealing and by forming solid solutions with perovskite compounds that exhibit normal dielectric behavior, such as Pb(Fe 1/2 Nb 1/2 )O 3 (PFN), PbZrO 3 (PZ) and PbTiO 3 (PT) [2].…”