Электрофизические и диэлектрические свойства поликристаллов железо-иттриевого феррита-граната, полученных по технологии радиационно-термического спекания

In this paper the electrical and dielectric properties of polycrystalline yttrium iron garnet, obtained by the radiation-thermal sintering technology in a fast electron beam were investigated. Spectra of complex dielectric constant, dielectric loss tangent and conductivity were measured in the frequency range 25 – 1∙106 Hz. For comparison, DC resistance measurements were also performed. The temperature dependences of the above parameters were measured at frequencies of 1 kHz, 100 kHz in the range 25 - 300 °C. It is shown, that conduction activations energy, permittivity, loss tangent and resistance vary significantly from sintering temperature in the range of 1300 to 1450 °C. It is found that with an increase in the sintering temperature to 1450 °C, dielectric properties are the same as samples made by the traditional ceramic technology.

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Effect of Sintering Temperature on Electrical and Dielectric Properties of Ni Based BaTiO3 Composite

Journal of Nanoelectronics and Optoelectronics ◽

10.1166/jno.2015.1755 ◽

2015 ◽

Vol 10 (3) ◽

pp. 386-390 ◽

Cited By ~ 3

Author(s):

Mohsin Saleem ◽

Jae Sung Song ◽

Insung Kim ◽

Min-Soo Kim ◽

Seok Myoung Jang ◽

...

Keyword(s):

Dielectric Properties ◽

Sintering Temperature ◽

Electrical And Dielectric Properties

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REVISIT TO DIELECTRIC PROPERTIES OF FERRITE CERAMICS

Journal of Advanced Dielectrics ◽

10.1142/s2010135x12300101 ◽

2012 ◽

Vol 02 (03) ◽

pp. 1230010 ◽

Cited By ~ 2

Author(s):

L. B. KONG ◽

L. LIU ◽

J. W. ZHAI ◽

Z. W. LI ◽

Z. H. YANG

Keyword(s):

Dielectric Properties ◽

Dielectric Loss ◽

Loss Tangent ◽

Dielectric Loss Tangent ◽

Sintering Temperature ◽

Short Review ◽

Sintering Aids ◽

Time Duration ◽

Sintering Aid ◽

Low Dielectric

Dielectric properties of ferrite ceramics have been less reported than their magnetic properties. Our recent study indicated that ferrite ceramics with very low dielectric loss tangent can be developed by using appropriate sintering aids, together with the optimization of other sintering parameters such as sintering temperature and time duration. Among various candidates of sintering aids, Bi 2 O 3 is the most promising one. It is important to find that the optimized concentration of sintering aid for full densification is not sufficient to achieve lowest dielectric loss tangent. This short review was aimed to summarize the understanding in microstructural evolution, grain growth, densification and dielectric properties of ferrite ceramics as a function of sintering aid concentration and sintering parameters, which could be used as a guidance to develop ferrite ceramics with low dielectric loss tangents for various applications.

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Effect of Sintering Temperature on Structure and Dielectric Properties of BZN Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.512-515.1203 ◽

2012 ◽

Vol 512-515 ◽

pp. 1203-1206

Author(s):

Yun Hui Xu ◽

Xiao Hong Zhu ◽

Qiang Zhang ◽

Jian Guo Zhu ◽

Ding Quan Xiao

Keyword(s):

Dielectric Properties ◽

Loss Tangent ◽

Room Temperature ◽

Sintering Temperature ◽

Microwave Frequency ◽

Fabrication Technology ◽

X Ray Diffraction ◽

X Ray ◽

Dielectric Constant And Loss ◽

Different Temperatures

Bismuth zinc niobate [(Bi1.5Zn0.5)(Nb1.5Zn0.5)O7, abbreviated as BZN] ceramics are receiving increasing attention due to their excellent dielectric properties in the microwave frequency range. This work is aimed at improving the fabrication technology of BZN ceramics. BZN ceramic specimens were prepared using the general electronic ceramic technique including milling, calcining, crushing, pressing, and sintering. Different sintering temperatures in the range of 950-1080°C were used to study how sintering temperature affects the structure and dielectric properties of BZN ceramics. The crystallinity and microstructure of the BZN ceramics, which were measured respectively by X-ray diffraction and scanning electron microscopy, were improved with increasing of the sintering temperature. The frequency dependence of the dielectric constant and loss tangent was measured at room temperature from 1 kHz to 1 MHz. The dielectric properties of the specimen sintered at 1050°C were found to be the best, for which the relative permittivity (εr) and the loss tangent (tanδ) are around 146 and 0.005, respectively. It was also foεund that when the sintering temperature was higher than 1000°C, the εrand the tanδ of BZN ceramics sintered at different temperatures were similar. As a result, 1000°C may be an appropriate sintering temperature for BZN ceramics.

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Influence of sintering temperature on electrical and dielectric properties of Mn (1 %) added MgCuZn ferrites

Indian Journal of Physics ◽

10.1007/s12648-013-0393-2 ◽

2013 ◽

Vol 88 (2) ◽

pp. 151-156 ◽

Cited By ~ 3

Author(s):

A. Bhaskar ◽

S. R. Murthy

Keyword(s):

Dielectric Properties ◽

Sintering Temperature ◽

Electrical And Dielectric Properties

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Synthesis and Pressure-Assisted Sintering of CaCu3Ti4O12 Dielectrics

Ceramics ◽

10.3390/ceramics4030033 ◽

2021 ◽

Vol 4 (3) ◽

pp. 447-466

Author(s):

Jan Pertášek ◽

Pavel Ctibor ◽

Josef Sedláček ◽

Frantisek Lukáč

Keyword(s):

High Pressure ◽

Phase Composition ◽

Dielectric Properties ◽

Loss Tangent ◽

Relative Permittivity ◽

Sintering Temperature ◽

Dielectric Behavior ◽

Feedstock Powder ◽

Dielectric Characteristics ◽

Conventional Sintering

In this paper, we examined the dielectric properties of CaCu3Ti4O12 (CCTO) ceramics fabricated by various routes and discussed the most important conditions affecting their dielectric behavior. We prepared feedstock powder using a molten salt route and compared it with a commercial powder. Both powders were sintered using SPS. For some samples, annealing was applied after sintering. Other samples were obtained by high-pressure forming and conventional sintering, using both powders. Phase composition, porosity and microhardness were evaluated in comparison with the literature. The results showed that a sintering temperature just below or equal to 1000 °C should be set for the SPS process. However, the best dielectric characteristics were obtained in samples prepared by high-pressure forming and conventional sintering, which showed a relative permittivity of 22,000 and a loss tangent of 0.13 at 1 MHz.

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The sintering temperature effects on the electrical and dielectric properties of Li[sub 0.05]Ti[sub 0.02]Ni[sub 0.93]O ceramics prepared by a direct thermal decomposition method

Journal of Applied Physics ◽

10.1063/1.2990768 ◽

2008 ◽

Vol 104 (7) ◽

pp. 074109 ◽

Cited By ~ 21

Author(s):

Prasit Thongbai ◽

Teerapon Yamwong ◽

Santi Maensiri

Keyword(s):

Thermal Decomposition ◽

Dielectric Properties ◽

Temperature Effects ◽

Decomposition Method ◽

Sintering Temperature ◽

Thermal Decomposition Method ◽

Electrical And Dielectric Properties

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BARIUM AND CALCIUM NIOBATE CERAMICS: SPECIFIC FEATURES OF THEIR STRUCTURE

Physical and Chemical Aspects of the Study of Clusters Nanostructures and Nanomaterials ◽

10.26456/pcascnn/2021.13.085 ◽

2021 ◽

pp. 85-95

Author(s):

Ольга Сергеевна Гусева ◽

Ольга Витальевна Малышкина ◽

Александра Ивановна Иванова ◽

Кристина Николаевна Бойцова

Keyword(s):

Dielectric Constant ◽

Dielectric Properties ◽

Elemental Composition ◽

Sintering Temperature ◽

Ferroelectric Properties ◽

Temperature Dependences ◽

Calcium Niobate

В работе получены и исследованы образцы керамики на основе ниобата бария - кальция CaBaNbO, с различным процентным соотношением бария и кальция (с x = 1; 0,9; 0,8; 0,7; 0,6; 0,5; 0,4; 0,3; 0,2; 0,1 и 0 ). Исследовано влияние температуры спекания на структуру и диэлектрические свойства керамики. Одна партия образцов спекалась при температуре 1100°С, вторая при температуре 1250°С. Показано, что температуры спекания 1100 °С не достаточно для получения хороших сегнетоэлектрических свойств, а процесс рекристаллизации зерен не завершен. Согласно исследованиям элементного состава, у образцов, спеченных при температуре 1250 °С с содержанием Ca≥0,5, атомы Ba присутствуют не во всех зернах, что оказывает влияние и на ход температурных зависимостей диэлектрической проницаемости. По диэлектрическим свойствам выделяется образец с x = 0,3. We obtained and studied the samples of ceramics based on barium niobate and calcium niobate CaBaNbO with different percentages of barium and calcium (x = 1; 0,9; 0,8; 0,7; 0,6; 0,5; 0,4; 0,3; 0,2; 0,1 and 0 ). The effect of the sintering temperature on the structure and dielectric properties of ceramics has been investigated. One batch of the samples was sintered at a temperature of 1100 °C, the second at 1250 °C. We have shown that the sintering temperature of 1100 °C is not enough to obtain good ferroelectric properties, and the process of grain recrystallization is not completed. According to studies of the elemental composition, in samples sintered at a temperature of 1250 °C with the Ca content greater than 0,5, Ba atoms are not present in all grains, which also affects the course of the temperature dependences of the dielectric constant A sample with x = 0,3 is distinguished by its dielectric properties.

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Characterization of A6 LTCC Systems for Microwave and Millimeter-Wave Applications

2003 International Electronic Packaging Technical Conference and Exhibition, Volume 2 ◽

10.1115/ipack2003-35134 ◽

2003 ◽

Author(s):

Liang Chai ◽

Aziz Shaikh ◽

Vern Stygar

Keyword(s):

Dielectric Constant ◽

Dielectric Properties ◽

Loss Tangent ◽

Low Cost ◽

Open Resonator ◽

Satellite Communications ◽

Wide Frequency Range ◽

Ceramic Technology ◽

Metal Loss ◽

Strip Line

Low Temperature Co-fired Ceramic (LTCC) materials are widely used in ceramic packaging and interconnect applications, such as RF receiving modules for next generation handsets and T/R modules for satellite communications. The application frequency spans from low GHz to 100+ GHz. A variety of techniques must be used to characterize dielectric properties (loss tangent and dielectric constant) of LTCC in the wide frequency range. These techniques include the parallel plate capacitor method from DC to several MHz, cavity methods in x-band, and open resonator techniques for frequencies up to 100+ GHz. LTCC is a multi-layer ceramic technology, which offers capability for low cost manufacturing, realizing 3D structures, and embedding passive components. Both strip line and microstrip types of transmission line structures can be conveniently manufactured using LTCC material systems. As an important performance parameter, microstrip loss can be characterized using the ring resonator technique. Both LTCC and metal conductors contribute to the microstrip loss. At microwave and mm-wave frequencies, metal losses become significant, although low resistance silver conductor can be used. The metal loss may be divided into two categories: one is the resistive loss and other is surface roughness loss. A photo imaging technique has been introduced which patterns the microstrip, reducing the surface loss. In this paper, the techniques for measuring both dielectric properties of A6 LTCC and microstrip properties of A6 LTCC with conductor systems will be reviewed. Characterization results of the dielectric constant and loss tangent of A6 from near DC to 100 GHz will be presented. Microstrip losses, measured for A6 LTCC with both gold and silver metallization up to 40 GHz, are compared to those computed using the closed form equations and experimentally determined dielectric and conductor properties. The calculated effective microstrip permitivity and attenuation compare well to those from measurements.

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