Effect of minor phase (CuO) on sinterability, grain size, and dielectric properties of CaCu3Ti4O12 ceramics

Broadband measurements of dielectric properties of natural snow samples near or at 0°C are reported. Measurement quantities are: dielectric permittivity, loss factor and complex propagation factor for electromagnetic waves. X-band measurements were made in a cold room in the laboratory; measurements at low and intermediate frequencies were carried out both in the field (Stubai Alps, 3300 m; Hafelekar near Innsbruck, 2100 m) and in the cold room. Results show that in the different frequency ranges the relative effect on snow dielectric properties of the parameters: density, grain-size and shape, liquid water content, shape and distribution of liquid inclusions and content of impurities, varies significantly. In the low-frequency range the influence of grain-size and shape and snow density dominates; in the medium-frequency range liquid water content and density are the dominant parameters. In the microwave X-band the influence of the amount, shape and distribution of liquid inclusions and snow density is more important than that of the remaining parameters.

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Grain-size-insensitive dielectric properties of Sr0.6Ba0.4Nb2O6 relaxor ferroelectric ceramics with tetragonal tungsten bronze structure

Ceramics International ◽

10.1016/j.ceramint.2021.11.233 ◽

2021 ◽

Author(s):

Mako Tsuchiya ◽

Shinobu Fujihara ◽

Manabu Hagiwara

Keyword(s):

Grain Size ◽

Dielectric Properties ◽

Tungsten Bronze ◽

Relaxor Ferroelectric ◽

Ferroelectric Ceramics ◽

Tungsten Bronze Structure ◽

Tetragonal Tungsten Bronze ◽

Relaxor Ferroelectric Ceramics

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Effects of grain size on the dielectric properties of Pb(Mg1/3Nb2/3)O3-30 mol % PbTiO3 ceramics

Journal of Applied Physics ◽

10.1063/1.2794377 ◽

2007 ◽

Vol 102 (7) ◽

pp. 074116 ◽

Cited By ~ 12

Author(s):

Wook Jo ◽

Tae-Hyeong Kim ◽

Doh-Yeon Kim ◽

Shyamal Kumar Pabi

Keyword(s):

Grain Size ◽

Dielectric Properties ◽

Pbtio3 Ceramics

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Effect of Sintering Temperature on Structure and Dielectric Properties of Lead Free K0.5Na0.5NbO3 Prepared via Hot Isostatic Pressing

Materials Science Forum ◽

10.4028/www.scientific.net/msf.888.42 ◽

2017 ◽

Vol 888 ◽

pp. 42-46 ◽

Cited By ~ 1

Author(s):

Fatin Khairah Bahanurdin ◽

Julie Juliewatty Mohamed ◽

Zainal Arifin Ahmad

Keyword(s):

Grain Size ◽

Dielectric Properties ◽

Room Temperature ◽

Sintering Temperature ◽

Hot Isostatic Pressing ◽

Solid State Reaction Method ◽

Lead Free ◽

Tangent Loss ◽

Isostatic Pressing ◽

Tan Δ

In this research, alkaline niobate known as K0.5Na0.5NbO3 (KNN) lead-free piezoelectric ceramic was synthesis by solid state reaction method which pressing at different sintering temperatures (1000 °C and 1080 °C) prepared via hot isostatic pressing (HIP)). The effect of sintering temperature on structure and dielectric properties was studied. The optimum sintering temperature (at 1080 °C for 30 minutes) using hot isostatic pressing (HIP) was successfully increase the density, enlarge the particle grain size in the range of 0.3 µm – 2.5 µm and improves the dielectric properties of K0.5Na0.5NbO3 ceramics. The larger grain size and higher density ceramics body will contribute the good dielectric properties. At room temperature, the excellent relative permittivity and tangent loss recorded at 1 MHz (ɛr = 5517.35 and tan δ = 0.954), respectively for KNN1080HIP sample. The KNN1080HIP sample is also exhibits highest relative density which is 4.485 g/cm3. The ɛr depends upon density and in this work, the density increase as the sintering temperature increase, which resulting the corresponding ɛr value also increases.

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Comparison of Grain Size Effects on Microstructure and Dielectric Properties of Y2/3Cu3Ti4-xFexO12(X = 0.00, 0.05 and 0.15) Ceramics Synthesized by Glycine Assisted Semi Wet Route

Processing, Properties, and Design of Advanced Ceramics and Composites: Ceramic Transactions ◽

10.1002/9781119323303.ch10 ◽

2016 ◽

pp. 117-130

Author(s):

S. Sharma ◽

M.M. Singh ◽

Narsingh B. Singh ◽

K.D. Mandal

Keyword(s):

Grain Size ◽

Dielectric Properties ◽

Size Effects ◽

Grain Size Effects

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The role of interfaces on an apparent grain size effect on the dielectric properties for ferroelectric barium titanate ceramics

Ferroelectrics ◽

10.1080/00150199808009168 ◽

1998 ◽

Vol 206 (1) ◽

pp. 337-353 ◽

Cited By ~ 291

Author(s):

M. H. Frey ◽

Z. Xu ◽

P. Han ◽

D. A. Payne

Keyword(s):

Grain Size ◽

Dielectric Properties ◽

Barium Titanate ◽

Size Effect ◽

Grain Size Effect ◽

Titanate Ceramics

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Structural and dielectric properties of Bi2NbxVi−xO5.5 ceramics

Journal of Materials Research ◽

10.1557/jmr.1996.0291 ◽

1996 ◽

Vol 11 (9) ◽

pp. 2288-2292 ◽

Cited By ~ 14

Author(s):

K. B. R. Varma ◽

K. V. R. Prasad

Keyword(s):

Differential Scanning Calorimetry ◽

Grain Size ◽

Dielectric Properties ◽

Curie Temperature ◽

Room Temperature ◽

Dielectric Constants ◽

Scanning Calorimetry ◽

Electron Microscopic ◽

Scanning Electron Microscopic ◽

Scanning Electron

Bi2Nbx V1−xO5.5 ceramics with x ranging from 0.01 to 0.5 have been prepared. The crystal system transforms from an orthorhombic to tetragonal at x 3= 0.1 and it persists until x = 0.5. Scanning electron microscopic (SEM) investigations carried out on thermally etched Bi2NbxV1−xO5.5 ceramics confirm that the grain size decreases markedly (18 μm to 4 μm) with increasing x. The shift in the Curie temperature (725 K) toward lower temperatures, with increasing x, is established by Differential Scanning Calorimetry (DSC). The dielectric constants as well as the loss tangent (tan δ) decrease with increasing x at room temperature.

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