Effect of MnO2 Impurity on the PZT-PMN System Ceramics for Piezoelectric Transformer

2008 ◽  
Vol 55-57 ◽  
pp. 189-192
Author(s):  
Y. Suwan ◽  
Anuson Niyompan ◽  
Rungnapa Tipakontitikul ◽  
Pitak Laoratanakul
Keyword(s):  
Dielectric Constant ◽  
Grain Size ◽  
Phase Transformation ◽  
Physical Properties ◽  
Temperature Dependence ◽  
Room Temperature ◽  
Piezoelectric Properties ◽  
Relative Dielectric Constant ◽  
Linear Shrinkage ◽  
Poling Process

The PZT-PMN ceramics system was derived from Pb(Zr0.5Ti0.5)O3 and Pb(Mg2/3Nb1/3)O3 based compositions those obtained via the columbite method. The effect of MnO2 addition on microstructure, physical properties and piezoelectric properties were investigated. In this study, the composition with PZT/PMN ratio of 1:1 was selected. To observe the effect of MnO2 adding, its concentration was varied in range 0-10 mol%. Green pellets were sintered at temperature 1250oC for 4 hours. For piezoelectric investigation, the ceramics pellets were subjected to a poling process. The XRD results show that there is no phase transformation observed for all sintered PZT-PMN samples with presence of MnO2. The SEM micrographs reveal that MnO2 can enhance sinterability as evidenced by lowering of porosity and increasing of grain size with increasing of MnO2 content. Increasing of linear shrinkage and apparent densities also confirmed such effect. Improvement of d33 from 28 to 114 pC/N could only found for MnO2 in range 0 to 4 mol%. For higher MnO2 content, there is only slightly increased. However, increasing of kp with increasing of MnO2 is clearly observed. While dielectric constant measured at room temperature and at frequency 1 kHz is higher for ceramics without MnO2 doping and it decreases with increasing MnO2 concentration. The temperature dependence of relative dielectric constant go to peak of value about 6000 at temperature around 180oC and shifting of these peaks with frequency can only be observed for samples with higher MnO2 content. This indicates a normal ferroelectric behavior for sample with lower MnO2 and there are converted to relaxor after MnO2 increased.

The Physical and Molecular Properties of New Low Melting Nematics with Negative Dielectric Anisotropy

1999 ◽  
Vol 54 (6-7) ◽  
pp. 448-452 ◽  
Author(s):  
R. Dąbrowski ◽  
J. Jadżyna ◽  
J. Dziaduszek ◽  
Z. Stolarz ◽  
G. Czechowski ◽  
...  
Keyword(s):  
Dipole Moment ◽  
Physical Properties ◽  
Temperature Dependence ◽  
Carboxylic Acids ◽  
Order Parameter ◽  
Room Temperature ◽  
Dielectric Anisotropy ◽  
Molecular Dipole ◽  
Nematic Order ◽  
Moment Vector

Abstract The paper presents some basic physical properties (static electric permittivities, refraction indices, density and viscosity) of 2-chloro-4-n’-alkylphenyl esters of 4-n-alkylbicyclo[2,2,2] octane-1-carboxylic acids (n’=7, n = 5 and 7) which are, at room temperature, nematics with a negative dielectric an-isotropy. On the basis of temperature dependence of the principal static permittivities ε‖(T) and e⊥(T) of the nematics, using the Maier-Meier equations, the angle between the dipole moment vector and the long axis of mesogenic molecules, the apparent molecular dipole moment square pl μ2app(T), and the nematic order parameter S(T) were determined.

Effect of MgAl2O4 Micrpowder on Physical Properties of Corundum Castables

2014 ◽  
Vol 633 ◽  
pp. 348-351
Author(s):  
Yao Sheng Hu ◽  
Ping An Chen ◽  
Bo Quan Zhu ◽  
Zheng Ma ◽  
Xiang Cheng Li
Keyword(s):  
Growth Rate ◽  
Physical Properties ◽  
Room Temperature ◽  
Raw Materials ◽  
Linear Shrinkage ◽  
Modulus Of Rupture ◽  
Crushing Strength ◽  
Heat Treated ◽  
Dispersion Agent ◽  
Aluminate Cement

Corundum-based castables were prepared by using tabular corundum, micropowder of MgAl2O4spinel and calcium aluminate cement as raw materials, as well as the addition of dispersion agent and retarder. The effect of spinel contents on physical properties of the castables has been investigated. The results showed that as the samples were heat treated at 1100 °C and 1600 °C, the linear shrinkage rate decreased and the strength of rupture and crushing at room temperature increased with spinel content increasing, while apparent porosity and bulk density remained the same. The hot modulus of rupture increased from 12 MPa to 20MPa with 67% growth rate, and crushing strength after thermal shock increased from 80MPa to 105MPa with 32% growth rate. The increasing of high-temperature properties was attributed to the staggered distribution between MgAl2O4spinel and CA6.

Dielectric Properties of Pulsed Excimer Laser Ablated BaBi2Nb2O9 Thin Films

2002 ◽  
Vol 748 ◽  
Author(s):  
Apurba Laha ◽  
S. B. Krupanidhi ◽  
S. Saha
Keyword(s):  
Thin Films ◽  
Phase Transition ◽  
Dielectric Constant ◽  
Temperature Dependence ◽  
Loss Tangent ◽  
Dielectric Response ◽  
Room Temperature ◽  
Dielectric Constant And Loss ◽  
Wide Range ◽  
Room Temperature Dielectric Constant

ABSTRACTThe dielectric response of BaBi2Nb2O9 (BBN) thin films has been studied as a function of frequency over a wide range of temperatures. Both dielectric constant and loss tangent of BBN thin films showed a ‘power law’ dependence with frequency, which was analyzed using the Jonscher's universal dielectric response model. Theoretical fits were utilized to compare the experimental results and also to estimate the value of temperature dependence parameters such as n(T) and a(T) used in the Jonscher's model. The room temperature dielectric constant (ε') of the BBN thin films was 214 with a loss tangent (tanδ) of 0.04 at a frequency of 100 kHz. The films exhibited the second order dielectric phase transition from ferroelectric to paraelectric state at a temperature of 220 °C. The nature of phase transition was confirmed from the temperature dependence of dielectric constant and sponteneous polarization,respectively. The calculated Currie constant for BBN thin films was 4 × 105°C.

Electrical Properties of Bi(In,Ga,Sc)O3-PbTiO3 Piezoelectric Ceramics

2013 ◽  
Vol 364 ◽  
pp. 794-798 ◽  
Author(s):  
Yi Chen ◽  
Jian Guo Zhu ◽  
Ding Quan Xiao
Keyword(s):  
Dielectric Constant ◽  
High Temperature ◽  
Electrical Properties ◽  
Lead Titanate ◽  
Room Temperature ◽  
Electromechanical Coupling ◽  
Piezoelectric Properties ◽  
Electromechanical Coupling Coefficient ◽  
Piezoelectric Devices ◽  
Dielectric And Piezoelectric Properties

The gallium and indium double-modified bismuth scandate-lead titanate (1-x)Bi (In0.20Ga0.05Sc0.75)O3-xPbTiO3((1-x)BIGS-xPT,x=0.55-0.70) ceramics were prepared by using conventional ceramic technique. (1-x)BIGS-xPT ceramics for nearx=0.60 exhibits an evident enhancement in room temperature dielectric and piezoelectric properties, with dielectric constantε, piezoelectric constantd33, planar electromechanical coupling coefficientkpand Curie temperatureTCof 1100, 295 pC/N, 0.43 and 435 °C, respectively. TheTCof (1-x)BIGS-xPT is in the range of 425-530 °C for the compositions investigated. The combination of highTCand excellent piezoelectric activity suggest that the (1-x)BIGS-xPT ceramics are usable candidate materials for high temperature piezoelectric devices applications.

Phase Formation and Grain Growth of BSCZT Ceramics Prepared by BST-BZT Seed Induced Method

2018 ◽  
Vol 766 ◽  
pp. 175-179
Author(s):  
Jiraporn Dangsak ◽  
Sukum Eitssayeam ◽  
Denis Russell Sweatman ◽  
Uraiwan Intatha
Keyword(s):  
Dielectric Constant ◽  
Grain Size ◽  
Phase Formation ◽  
Room Temperature ◽  
Single Phase ◽  
Seed Crystal ◽  
Lead Free ◽  
X Ray Diffraction ◽  
X Ray ◽  
Density Values

In this work, lead-free Ba0.4Sr0.4Ca0.2Zr0.05Ti0.95O3 ceramics were prepared by the seed induced method using (0.5Ba0.6Sr0.4TiO3–0.5BaZr0.05Ti0.95O3) (BST-BZT) seed. Seed crystals with concentrations of 0, 2.5, 5, 7.5, 10 mol% were mixed with BSCZT powder for 24 h and sintered at 1400 °C for 4 h. The phase formation and microstructure of BSCZT ceramic were characterized by X-ray diffraction technique (XRD) and the scanning electron microscopy (SEM). All samples showed a single phase perovskite structure without impurities and exhibited the existence of the tetragonal phase. The density values of the ceramics decreased from 4.90 to 4.75 g/cm3 with increasing seed crystal concentrations. The grain size of the sample without seed was 3.71 μm, whereas a grain size of 8.99 μm was observed for the sample with 10 mol% seed crystal. The dielectric constant at room temperature at 1 kHz was 1831 for the sample with 10 mol% seed crystal while the dielectric constant of the sample without seed was 1484. From the results in this work, BST-BZT seed can increase grain size and improve the dielectric constant at room temperature.

Dielectric and Magnetic Properties of Sintered Cobalt Ferrite Derived from Nanocrystalline Powders

2012 ◽  
Vol 476-478 ◽  
pp. 726-729 ◽  
Author(s):  
Liang Neng Wu ◽  
Li Zhen Jiang ◽  
Fang Yu Hong
Keyword(s):  
Dielectric Constant ◽  
Magnetic Properties ◽  
Hysteresis Loop ◽  
Loss Tangent ◽  
Room Temperature ◽  
Cobalt Ferrite ◽  
Relative Dielectric Constant ◽  
Nanocrystalline Powders ◽  
Magnetic Characteristics ◽  
Dielectric Constant And Loss

A kind of Cobalt ferrite ceramics were successfully prepared by using nanocrystalline powders synthesized by citrate gel method. The relative dielectric constant and loss tangent of the ceramic as a function of frequency (100 Hz - 1 MHz) was investigated at room temperature. Both of them decrease with increase in frequency showing dispersion. Hysteresis loop magnetization was measured and the ceramic show good magnetic characteristics at room temperature.

Physical properties of spinel iron oxide thin films

1988 ◽  
Vol 3 (2) ◽  
pp. 344-350 ◽  
Author(s):  
C. Ortiz ◽  
G. Lim ◽  
M. M. Chen ◽  
G. Castillo
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Grain Size ◽  
Physical Properties ◽  
Room Temperature ◽  
Lattice Parameter ◽  
Infrared Transmission ◽  
Transmission Properties ◽  
Annealing Conditions ◽  
Deposition Conditions

This paper describes the complexity of the spinel iron oxides in thin-film configuration. First, the experimental deposition conditions are determined for the parameters of substrate temperature and oxygen flow such that only the “Fe3O4” phase is formed. Then a study is made of how the structural (grain size, lattice parameter, texture), magnetic (M), and optical (visible and infrared transmission) properties of the films depend on the deposition and postdeposition (air annealing) conditions. The experimental deposition region is defined where the films have the most similar physical properties to bulk Fe3O4 and subsequently, after annealing, to bulk gamma Fe2O3. Finally, a discussion is presented of a model that accounts for the anomalous, low values of the magnetic moment for the samples deposited at room temperature. The model proposes an overpopulation of the iron tetrahedral A sites.

Temperature dependence of piezoelectric properties of 0.67 Pb(Mg1/3Nb2/3)O3–0.33 PbTiO3 single crystals

2003 ◽  
Vol 18 (2) ◽  
pp. 537-541 ◽  
Author(s):  
Ping-chu Wang ◽  
Xiao-ming Pan ◽  
Dong-lin Li ◽  
Yuan-wei Song ◽  
Hao-su Luo ◽  
...  
Keyword(s):  
Phase Transition ◽  
Transition Temperature ◽  
Temperature Dependence ◽  
Single Crystals ◽  
Phase Transition Temperature ◽  
Room Temperature ◽  
Piezoelectric Properties ◽  
Device Design ◽  
Temperature Range ◽  
Approach Zero

Piezoelectric properties k33 and d33 of 0.67 Pb(Mg1/3Nb2/3)O3–0.33 PbTiO3 single crystals grown by a modified Bridgman method were measured in the temperature range of 20–150 °C. Recoverability of the properties after the samples were heated to 110 °C, above the ferroelectric–ferroelectric (F–F) phase transition temperature of the composition, was found. From 20 to approximately 80 °C, k33 increases slightly, while d33 is almost doubled. Between approximately 90 and 100 °C, k33 decreases sharply to roughly a level of PZT-5 ceramics and d33 decreases to about 700 pC/N. They increase again with further increase of temperature; at 140 °C they attain 0.74 and approximately 1300 pC/N, respectively, and then decrease quickly and approach zero at about 150 °C. When heating to 110 °C followed by cooling to room temperature, the property decay is small. After more than one dozen heating–cooling cycles, k33 and d33 tend to be stable at 0.89 and approximately 1220 pC/N, respectively. The results might be helpful for device design and applications of PMN–PT single crystals.

The Effects of Sintering Temperature Variations on some Physical Properties of Al2O3-SiO2-PbO-MgO Laminated Tape System

2009 ◽  
Vol 421-422 ◽  
pp. 285-288
Author(s):  
Rosidah Alias ◽  
Ibrahim Azmi ◽  
Sabrina Mohd Shapee ◽  
Zulkifli Ambak ◽  
Zulfadli Mohamed Yusoff ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Grain Size ◽  
Dielectric Loss ◽  
Physical Properties ◽  
Sintering Temperature ◽  
Temperature Variations ◽  
Sem Micrographs ◽  
Grain Sizes ◽  
Average Grain Size ◽  
Tape System

An Al2O3-SiO2-PbO-MgO laminated tape system was prepared to investigate the dependence of some physical properties on various sintering temperatures, 840 °C, 880 °C, 920 °C and 960 °C. The results show that the effect of the increasing sintering temperatures was a fluctuating in the density value of the laminates. It was also observed that the dielectric constant and dielectric loss showed the lowest value for the sintering temperature of 880 °C. SEM micrographs of the laminate samples shows a mixture of grain sizes and the samples had a combination of small and large pores with the average grain size around 2.20-2.64 m.

Temperature Stable Bi1.3Yb0.7O3-BaTiO3 Relaxor Ferroelectric

2011 ◽  
Vol 415-417 ◽  
pp. 1046-1050
Author(s):  
Jun Ting Qi ◽  
Jun Jie Hao ◽  
Yun Xia Zhang ◽  
Bo Liu ◽  
Xiao Jia Wang
Keyword(s):  
Dielectric Constant ◽  
Grain Size ◽  
Dielectric Loss ◽  
Diffraction Method ◽  
Relative Dielectric Constant ◽  
Relaxor Ferroelectric ◽  
X Ray Diffraction ◽  
Low Dielectric ◽  
Fracture Morphologies ◽  
Thermal Stability Of

A new system, Bi1.3Yb0.7O3-BaTiO3 was found as a perovskite dielectrics with some advantageous properties. The structure was identified by X-ray diffraction method and SEM was also employed to observe the surface and fracture morphologies. The studies indicate that the relative dielectric constant initially increases and then decreases slightly, the dielectric loss initially decreases and finally close to a stable value. The experimental results reveal that the grain size became smaller initially, then increase after the sample E and finally the sample F had the maximum grain size. Experiments show the system Bi1.3Yb0.7O3-BaTiO3 can significantly improve the thermal stability of the BaTiO3 ceramics. Electric hysteresis loop show that the system is relaxor ferroelectric. The samples doped with 20% BiYbO3 calcined at 750°C for 2h and then sintered at 1280°C for 2h exhibited attractive properties, including high relative dielectric constant (>1000), low dielectric loss (<2.5%), low temperature coefficient of capacitor (<±15%) over a wide temperature range from －55°C to +180°C, satisfying EIA X8R specifications.

Sign in / Sign up

Export Citation Format

Share Document