The Influences of NaNbO3 on the Dielectric and Structure Characteristics of (1-X) (Na0.5Bi0.5)TiO3–x NaNbO3 Ceramics

2011 ◽  
Vol 415-417 ◽  
pp. 1064-1069 ◽  
Author(s):  
Chia Ching Wu ◽  
Ying Hsun Lin ◽  
Ping Shou Cheng ◽  
Chao Chin Chan ◽  
Cheng Fu Yang
Keyword(s):  
Dielectric Constant ◽  
Ferroelectric Properties ◽  
Rhombohedral Structure ◽  
X Ray Diffraction ◽  
Depolarization Temperature ◽  
Dielectric Characteristics ◽  
X Ray ◽  
Maximum Dielectric Constant ◽  
Second Phases ◽  
Xrd Patterns

Perovskite-based (1-x) (Na0.5Bi0.5)TiO3-x NaNbO3 [(1-x) NBT-x NN, x = 0.1, 0.2, 0.3 and 0.4] ceramics were sintered at 1080°C. Dielectric characteristics, crystalline structures, and Raman investigations were carried out on (1-x) (Na0.5Bi0.5)TiO3-x NaNbO3 ceramics. X-ray diffraction (XRD) patterns showed that NaNbO3 ceramic would form a solid solution with (Na0.5Bi0.5)TiO3 ceramic, and and unknown or second phases were not observable as well. NaNbO3 ceramic diffused into the crystalline structure of (Na0.5Bi0.5)TiO3 ceramic and (1-x) NBT-x NN ceramics still revealed a rhombohedral structure. The temperature-dielectric constant curves showed that as NN content increased, the temperature to reveal the maximum dielectric constant (Tm) was raised, the depolarization temperature (Td) was shifted to lower value, and the dielectric constant at Tm and the loss tangent at Td gradually decreased. The Raman bands at 770 and 830 cm-1 were attributed to the existence of the oxygen vacancies. In this study, the relaxor-type ferroelectric properties of NBT ceramic had been improved as NN ceramic was added.

scholarly journals Dielectric and Ferroelectric Properties of Lead-Free[1-z{(Bi1-xLax)0.5(Na1-yLiy)0.5TiO3}-zBaTiO3]Ceramic System

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Vijayeta Pal ◽  
R. K. Dwivedi ◽  
O. P. Thakur
Keyword(s):  
Dielectric Constant ◽  
Ferroelectric Properties ◽  
Dissipation Factor ◽  
Lead Free ◽  
Rhombohedral Structure ◽  
Nonlinear Behaviour ◽  
Ceramic System ◽  
Low Dielectric ◽  
Maximum Dielectric Constant ◽  
Xrd Patterns

Lead-free specimens of [1-z{(Bi1-xLax)0.5(Na1-yLiy)0.5TiO3}-zBaTiO3] (BLNLT-BT, wherex=0.04,y=0.025, andz=0, 0.02, 0.04, and 0.06) ceramic system were synthesized by a semiwet technique. In the present study, we have investigated the effect of Ba on the structure, morphology, and dielectric, ferroelectric, and piezoelectric properties of BLNLT system. The XRD patterns of all the specimens showed rhombohedral structure at room temperature. Field emission scanning electron microscopy images (FE-SEM) showed grain growth inhibition with Ba content in BLNLT system. The temperature dependence of dielectric constant revealed that the temperature of maximum dielectric constant “Tm” and depolarization temperature “Td” decreased for the samplez=0.06and showed high value of dielectric constant with low dielectric loss. These samples exhibited nonlinear behaviour of hysteresis loop. The values of dielectric constant (εr), dissipation factor (tan δ), piezo charge coefficient (d33), remnant polarization (Pr), and coercive field (Ec) for the compositionz=0.06were 1495, 0.06, 20 pC/N, 5 μC/cm2, and 10.5 kV/cm, respectively.

scholarly journals ENHANCED FERROELECTRICITY AND FERROMAGNETISM OF (Y, Ni) CO-DOPED BiFeO3 MATERIALS

2018 ◽  
Vol 56 (1A) ◽  
pp. 219
Author(s):  
Dao Viet Thang
Keyword(s):  
Ferroelectric Properties ◽  
Sol Gel ◽  
Rhombohedral Structure ◽  
Ferromagnetic Behavior ◽  
X Ray Diffraction ◽  
X Ray ◽  
Co Doping ◽  
Saturation Polarization ◽  
Perovskite Type ◽  
Co Doped

In this study, multiferroicMultiferroic Bi1-xYxFe0.975Ni0.025O3 (x = 0.00, 0.05, 0.10, and 0.15) called as (Y, Ni)                co-doped BiFeO3 materials were synthesized by a sol-gel method.  and characterized by X-ray diffraction diagrams and(XRD), energy-dispersive X-ray (EDX) and vibrating sample magnetization (VSM) measurements demonstrated. The result showed that Bi1-xYxFe0.975Ni0.025O3all investigated materials waspresent a single phase of the perovskite-type rhombohedral structure. Ferromagnetism and ferroelectricity of the Bi1-xYxFe0.975Ni0.025O3 materials have been investigated. Results showed that the co-doping by (Y, Ni) for (Bi, Fe)  have affected in enhancing by the (Y, Ni) co-doping, as a result the ferroelectric polarization and magnetization of BiFeO3. The magnetic characterization indicated that the ferromagnetic behavior wasthe initial BiFeO3 materialwere enhanced with increasing concentration of Y3+ for (Y, Ni) co-substituted of BiFeO3. Which could beion. It is attributed to the defferentdifference of the magnetic momentmoments of Ni2+ and Fe3+, and+ ions, as well as the Y3+-Fe3+,+ and Y3+-Ni2+ super-exchange interaction. Theinteractions. The characteristics of the investigated materials, such as remanent magnetization (Mr), saturation magnetization (Ms), remanent polarization (2Pr) and saturation polarization (2Ps) continuously increase upon increasing in the range of x from 0.00 to 0.15. When x = 0.15, the values of Mr and Ms are 0.078 and 0.794 emu/g, respectively. The values of 2Pr and 2Ps are 16.58 and 27.99 µC/cm2, respectively. Origin of ferromagnetic and ferroelectric properties of Bi1-xYxFe0.975Ni0.025O3 materials will be discussed in this paper.

Electrical Properties of Modified BNT Based Lead-Free Ceramics

2016 ◽  
Vol 872 ◽  
pp. 87-91
Author(s):  
Supalak Manotham ◽  
Tawee Tunkasiri ◽  
Pharatree Jaita ◽  
Pichitchai Butnoi ◽  
Denis Russell Sweatman ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Solid State ◽  
Electrical Properties ◽  
Sintering Temperature ◽  
Ferroelectric Properties ◽  
Lead Free ◽  
Second Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lead Free Ceramics

The properties of modified Bi0.5Na0.5TiO3 (BNT) based lead-free ceramics were investigated. The BNT-based ceramics were prepared by a solid-state mixed oxide method Phase formation was determined by X-ray diffraction technique (XRD). The X-ray diffraction analysis of the ceramics suggested that all samples exhibited a perovskite structure without second phase. The value of dielectric constant increased with increasing in sintering temperature. Moreover, high sintering temperatures could improve ferroelectric properties of BNT base lead-free ceramics.

scholarly journals Dielectric properties of BNT-xBT prepared by hydrothermal process

2017 ◽  
Vol 07 (03) ◽  
pp. 1750019 ◽  
Author(s):  
Natheer B. Mahmood ◽  
Emad K. Al-Shakarchi
Keyword(s):  
Strong Dependence ◽  
Average Particle Size ◽  
Hydrothermal Process ◽  
Industrial Applications ◽  
Rhombohedral Structure ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Depolarization Temperature ◽  
X Ray ◽  
Ceramic Disc

The BNT ceramic sample might be a good replacement for PZT piezoelectric in industrial applications, especially in energy harvesting from crystal vibrations. In order to enhance the performance of BNT ceramic, the solid solution was chosen by substitution with Ba[Formula: see text] at Morphtropic Phase Boundary (MPB). The BNT-[Formula: see text]BT powders with [Formula: see text], 0.07, 0.06 and 0 were prepared by the hydrothermal method with average particle size (65–150[Formula: see text]nm) at (90[Formula: see text]C/72[Formula: see text]h). The ceramic disc was sintered at (1150[Formula: see text]C/4[Formula: see text]h) and showed excellent relative density of about 96%. The results of X-ray diffraction (XRD) confirmed the MPB for [Formula: see text] and 0.07, while the BNT had a rhombohedral structure and BT had a tetragonal structure. The dielectric measurements showed that BNT, BNT-7BT, BNT-6BT behave as the relaxator ferroelectric and showed a strong dependence on frequency, especially in the MPB region while BT behaves as a normal ferroelectric. Both the Curie temperature and depolarization temperature decrease at the MPB region and showed strong dependency on frequency.

scholarly journals Investigations on Structural, Mechanical, and Dielectric Properties of PVDF/Ceramic Composites

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Anshuman Srivastava ◽  
Karun Kumar Jana ◽  
Pralay Maiti ◽  
Devendra Kumar ◽  
Om Parkash
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Single Phase ◽  
Extrusion Process ◽  
Ceramic Composites ◽  
X Ray Diffraction ◽  
Composite State ◽  
X Ray ◽  
Embedded Capacitor ◽  
Xrd Patterns

Polymer ceramic composites are widely used for embedded capacitor application. In the present work PVDF has been used as a matrix and CCTO and LaCCTO have been used as reinforcement. Extrusion process has been used for the synthesis of composites. X-ray diffraction (XRD) patterns confirm the formation of single phase CCTO, and LaCCTO in its pure as well as composite state. It is found that La doping in CCTO considerably increases the dielectric constant and reduces the dielectric loss. A similar trend is observed in the composites with the increasing content of CCTO and LaCCTO.

scholarly journals Effect of Mn3O4 on the Dielectric Characteristics of Cdo - Mn3O4 Nanocomposites

2019 ◽  
Vol 8 (11) ◽  
pp. 1285-1290
Keyword(s):  
Thermal Decomposition ◽  
Dielectric Constant ◽  
High Temperature ◽  
Nano Composites ◽  
Conductivity Measurements ◽  
X Ray Diffraction ◽  
Dielectric Parameters ◽  
Dielectric Characteristics ◽  
X Ray ◽  
Lcr Meter

Undoped CdO, Mn3O4 and CdO - Mn3O4 doped nanocomposites in the ratio 9:1, 8:2, 7:3 and 6:4 were successfully synthesized through thermal decomposition at high temperature by adopting the method of solid state reaction. powder X-ray diffraction (PXRD) was employed to carry out the structural characterization. It was found that as the concentration of Mn3O4 was increased the size of the prepared CdO-Mn3O4 composites has decreased. The change of various dielectric variables like dielectric loss (tanδ), dielectric constant (εr ) was determined. Moreover the change of ac conductivity (σac) with respect to frequency was carried out using LCR meter. It was found that these dielectric parameters have increased with respect to the temperature. It was also found that, with an increase in temperature the dc conductivity measurements for the prepared nano composites have also increased

Phase Structure and Electrical Properties of Bi1/2Na1/2TiO3-KNbO3 Lead-Free Piezoelectric Ceramics

2007 ◽  
Vol 336-338 ◽  
pp. 184-187 ◽  
Author(s):  
Wen Zhong Lu ◽  
Gui Fen Fan ◽  
Xiao Hong Wang ◽  
Fei Liang
Keyword(s):  
Dielectric Constant ◽  
Electrical Properties ◽  
Piezoelectric Properties ◽  
Extreme Values ◽  
Piezoelectric Ceramics ◽  
Lead Free ◽  
Fabrication Technique ◽  
X Ray Diffraction ◽  
Depolarization Temperature ◽  
X Ray

Lead-free (1-x) Bi1/2Na1/2TiO3-xKNbO3 (x=0, 0.01, 0.02, 0.04, 0.05 0.06, 0.10) piezoelectric ceramics were prepared by conventional ceramics fabrication technique. The results of x-ray diffraction (XRD) show that these ceramics possess pure perovskite structures with a symmetry transition from rhombohedral to cubic at about x = 0.05. The piezoelectric properties of these ceramics were reported and found to reach extreme values at x = 0.04 with d33 up to 113pC/N and kp up to 22%. The temperature dependence of dielectric constant and dielectric loss of these ceramics were also investigated. The Curie temperature and depolarization temperature dropped with the increase of KNbO3 amount.

The Electrical and Physical Properties of (Ba0.7Sr0.3)(Ti0.9Zr0.1)O3 Thin Films under Conventional Annealing Process

2010 ◽  
Vol 434-435 ◽  
pp. 271-274
Author(s):  
Kai Huang Chen ◽  
Cheng Fu Yang ◽  
Chien Chen Diao
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Physical Properties ◽  
Leakage Current ◽  
Leakage Current Density ◽  
Current Density ◽  
X Ray Diffraction ◽  
Maximum Dielectric Constant ◽  
Xrd Patterns ◽  
Conventional Annealing

In this study, conventional furnace annealing (CFA) is used as the post-treated process, the effects of annealing temperatures on the crystallization and microstructure of (Ba0.7Sr0.3)(Ti0.9 Zr0.1)O3 (BSTZ) thin films will be developed, and the further influences on the electrical properties of BSTZ thin films are also investigated. A previous study made in our laboratory had shown that the dielectric constant and leakage current density of BSTZ thin film with 640 nm thickness are 192 and 10-6 A/cm2 under the frequency of 100 KHz, respectively. However, the maximum dielectric constant and minimum leakage current density of BSTZ thin films under CFA process are 420 (annealed at 800oC) and 10-8 A/cm2 (700oC), respectively. Besides, the X-ray diffraction (XRD) patterns and the SEM morphology show that crystalline features and grain size of BSTZ thin films increase with the increase of CFA-treated temperatures. These experiment results suggest that a strong correlation exhibits that the physical properties will influence the dielectric properties and nucleation features of BSTZ thin films.

Ferroelectric Properties of Bi0.5(Na0.8K0.2)0.5TiO3 Ceramics

2014 ◽  
Vol 975 ◽  
pp. 3-8 ◽  
Author(s):  
Javier Camargo ◽  
Leandro Ramajo ◽  
Fernando Rubio-Marcos ◽  
Miriam Castro
Keyword(s):  
Sintering Temperature ◽  
Ferroelectric Properties ◽  
Secondary Phase ◽  
Processing Conditions ◽  
Secondary Phases ◽  
X Ray Diffraction ◽  
Ceramic Powders ◽  
Density Measurements ◽  
X Ray ◽  
Xrd Patterns

Different processing conditions and the effect of secondary phases on ferroelectric properties of Bi0.5(Na0.8K0.2)0.5TiO3(BNKT) are studied. Ceramic powders are prepared by solid state reaction and different sintering temperatures (temperatures between 1075 and 1150°C) are analyzed. Finally, samples are characterized by X-ray diffraction, Raman microspectroscopy, Scanning Electron Microscopy, impedance spectroscopy, and density measurements. Through XRD patterns, the perovskite structure is stabilized; together with small peaks corresponding to a secondary phase associated with K2-xNaxTi6O13phase. Moreover, the content of the secondary phase, d33piezoelectric constant and dielectric properties increase with sintering temperature.

Dielectric, Piezoelectric and Magnetic Properties of Ferroelectromagnet Pb(Fe1/3Nb2/3)O3(PFN) Ceramics

2003 ◽  
Vol 17 (18n20) ◽  
pp. 3732-3737 ◽  
Author(s):  
Jin. T. Wang ◽  
Marx K. Mbonye ◽  
Cheng Zhang
Keyword(s):  
Crystal Structure ◽  
Dielectric Constant ◽  
Magnetic Properties ◽  
Transition Temperature ◽  
Dielectric Loss ◽  
Room Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Maximum Dielectric Constant ◽  
Piezoelectric Strain

Ferroelecromagnet Pb ( Fe 1/3 Nb 2/3) O 3 has been synthesized and its crystal structure and dielectric, electrostrictive and magnetic properties have been investigated. The structure of PFN ceramics examined by X-ray diffraction was found perovskite-like. The dielectric constant and dielectric loss as a function of temperature at different frequencies was measured. A para-ferroelectric transition at a temperature of 403 K was found and the maximum dielectric constant at a frequency of 500 Hz at the transition temperature is as high as 9050. The piezoelectric strain at room temperature was examined. The magnetization measurements as a function of temperature in the temperature region from room temperature to 648 K with different applied magnetic fields revealed that the compound is antiferromagnetic.

Sign in / Sign up

Export Citation Format

Share Document