Lead zirconate titanate

About: Lead zirconate titanate is a research topic. Over the lifetime, 7141 publications have been published within this topic receiving 150878 citations.

The effect of external field symmetry on the antiferroelectric‐ferroelectric phase transformation

Abstract: The antiferroelectric (AFE)‐ferroelectric (FE) phase transformation under dc bias and hydrostatic pressure conditions in tin‐modified lead zirconate titanate ceramics [Pb(Zr,Sn,Ti)O3, i.e., PZST] was investigated. The shifting of transformation temperature under these conditions and an electric field induced lattice softening are reported. Depending on the symmetry of external applied fields, the thermal stability region of one phase can be expanded at the expense of another. Experimental results indicate that a symmetric external field (such as hydrostatic pressure) tends to stabilize the AFE phase region, whereas an asymmetric external field (such as electric field) tends to extend the FE phase region. These observations are found to be generally consistent with many ferroelectric and antiferroelectric materials exhibiting a displacive structural phase transformation. Results are compared with the Clausius–Clapeyron relationship, and fundamental issues underlying the thermodynamic relationship and field...

Spontaneous Trasition between Relaxor and Ferroelectric States in Lanthanum-Modified Lead Zirconate Titanate (6–7)/65/35

Abstract: Dielectric and light scattering measurements are performed in lanthanum modified lead zirconate titanate (PLZT) (6–8)/65/35 hot-pressed ceramics in order to refine the phase diagram. A relaxor-ferroelectric phase transition takes place in PLZT (6–7)/65/35 at temperature lower than the temperature of the dispersive dielectric constant maximum. At this temperature the size of polar regions "a" essentially increases up to a>λ (=0.63 µ m). The appearence of ferroelectric long-range order in PLZT with decreased concentration of La ions is explained by larger coupling between ferroelectrically active BO6 octahedrons due to the smaller concentration of defects and higher dielectric constant.

Effect of Pb Content in Target on Electrical Properties of Laser Ablation Derived Lead Zirconate Titanate Thin Films

Abstract: Thin films of Pb(Zr0.52Ti0.48)O3(PZT) 1.8–2.0 µm thick on a Pt/Ti/SiO2/Si substrate were prepared by excimer laser ablation and were crystallized by subsequent annealing. Crystalline phases in the PZT films were investigated by X-ray diffraction analysis (XRD). The microstructure and composition of the films were studied by scanning electron microscopy (SEM) and electron probe microanalysis (EPMA), respectively. The effect of the Pb content of the target on electrical properties of PZT thin films was investigated. The PZT films with a well-crystallized perovskite phase were obtained by adding 20 wt.% excess PbO to the target and annealing at 750°C for 90 min. The remanent polarization and the coercive field of this 0.8 µm think film were 23.6 µC/cm2 and 60.0 kV/cm, while the dielectric constant and loss values measured at 1 kHz were approximately 935 and 0.04, respectively.

Poling of Lead Zirconate Titanate Ceramics and Flexible Piezoelectric Composites by the Corona Discharge Technique

Abstract: In the conventional poling method, piezoelectric ceramics and composites are poled by applying a large dc voltage. Poling of composites having a polymer matrix with 0–3 connectivity is especially difficult because the electric field within the high-dielectricconstant grains is far smaller than in the low-dielectric-constant polymer matrix. Therefore, very large electric fields are required to pole these types of composites. However, large electric fields often cause dielectric breakdown of the samples. In this study for improved poling, the corona discharge technique was used to pole piezoelectric ceramics, fired PZT composites, and 0.5PbTiO3· 0.5BiFeO3 0–3 polymer composites. An experimental setup for corona poling is described. The dielectric and piezoelectric properties of materials poled by the corona discharge technique were comparable to those obtained with the conventional poling method.

Derivation of Piezoelectric Losses from Admittance Spectra

Abstract: High power density piezoelectrics are required to miniaturize devices such as ultrasonic motors, transformers, and sound projectors. The power density is limited by the heat generation in piezoelectrics, therefore, clarification of the loss mechanisms is necessary. This paper provides a methodology to determine the electromechanical losses, i.e., dielectric, elastic and piezoelectric loss factors in piezoelectrics by means of a detailed analysis of the admittance/impedance spectra. This method was applied to determine the piezoelectric losses for lead zirconate titanate ceramics and lead magnesium niobate-lead titanate single crystals. The analytical solution provides a new method for obtaining the piezoelectric loss factor, which is usually neglected in practice by transducer designers. Finite element simulation demonstrated the importance of piezoelectric losses to yield a more accurate fitting to the experimental data. A phenomenological model based on two phase-shifts and the Devonshire theory of a polarizable–deformable insulator is developed to interpret the experimentally observed magnitudes of the mechanical quality factor at resonance and anti-resonance.