The Synthesis of CaCu3Ti4O12 High Dielectric Ceramics by a Spark Plasma Sintering Method

CaCu3Ti4O12 (CCTO) ceramics were synthesized by a spark plasma sintering technique, and then were annealed in air at different temperatures. The characterization methods including X-ray diffraction, X-ray photoelectron spectroscopy indicated that the composition distribution, the valance of the Ti ions of the CCTO ceramics have great dependence on the annealing temperature, which result in that the dielectric properties of the CCTO ceramics have great dependence on the annealing temperature. The annealing at 500 and 700 °C can enhance the dielectric constants greatly, and the dielectric loss at high frequence (1 MHz) reduces with the increase of the annealing temperature. These annealing-dependent dielectric properties are ascribed to the oxygen vacancies and the holes formed in the sintering and annealing treatment.

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Preparation and Magnetic Properties of Dense NiCuZn Ferrite by Spark Plasma Sintering

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.601 ◽

2008 ◽

Vol 368-372 ◽

pp. 601-603

Author(s):

Xi Wei Qi ◽

Ji Zhou ◽

Zhen Xing Yue ◽

Ming Ya Li ◽

Xiu Mei Han

Keyword(s):

Spark Plasma Sintering ◽

Annealing Temperature ◽

Annealing Treatment ◽

Impurity Phase ◽

Uniaxial Pressure ◽

Plasma Sintering ◽

Average Grain Size ◽

Conventional Sintering ◽

Spark Plasma ◽

Nicuzn Ferrite

Dense NiCuZn ferrites consisting of fine grains were prepared by spark plasma sintering (SPS) at 750°C for 3 min under a uniaxial pressure of 15 MPa. The powders were densified to >95% of theoretical density by the SPS process, and the average grain size of the prepared NiCuZn ferrite was < 1 /m. The saturation magnetization of prepared specimens (without further annealing treatment) was approximate 50.54 emu/g, which was slightly smaller than that of 52.21 emu/g for specimens prepared by conventional sintering at 980°C for 4 h. Phase identifications indicated that prepared NiCuZn ferrite existed impurity phase (Cu2O), and Cu2O would gradually transform to CuO when annealing temperature increased.

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Ordered Domains and Microwave Properties of Sub-micron Structured Ba(Zn1/3Ta2/3)O3 Ceramics Obtained by Spark Plasma Sintering

Materials ◽

10.3390/ma12040638 ◽

2019 ◽

Vol 12 (4) ◽

pp. 638

Author(s):

Fei Liu ◽

Shaojun Liu ◽

Xuejiao Cui ◽

Lijin Cheng ◽

Hao Li ◽

...

Keyword(s):

Spark Plasma Sintering ◽

Annealing Temperature ◽

Microwave Dielectric Ceramics ◽

X Ray Diffraction ◽

X Ray ◽

Microwave Dielectric ◽

Plasma Sintering ◽

Transmission Electron ◽

Spark Plasma ◽

Dielectric Ceramics

The degree of Zn2+ and Ta5+ ions ordering could play an important role in the dielectric loss in Ba(Zn1/3Ta2/3)O3 (BZT) ceramics. However, the influence of the grain size of Ba(B′1/3B″2/3)O3 ceramics with nano or sub-micron grains on the ordering domains structure is still not clear. In the present paper, highly dense (~98%) BZT microwave dielectric ceramics with homogeneous sub-micron structure (~330 nm) were prepared through spark plasma sintering (SPS). High resolution transmission electron microscopy combined with X-ray diffraction (XRD)clearly showed that the B-site ordering structure of sintered BZT samples by SPS becomes the B-site long-range 1:2 ordering as annealing proceeds. In contrast, the short-range 1:2 ordering in non-annealed counterparts was also present, which was not detectable by XRD. The size of B-site ordering domains enlarged with annealing temperature. The sub-micron structure of sintered BZT ceramics by SPS remained stable at up to 1400 C; however, the size of B-site 1:2 ordering domain was more than five times larger, which led to a significant increase of the quality factor (Q·f) to 37,700 GHz from 15,000 GHz.

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Dielectric properties of fine-grained BaTiO3 prepared by spark-plasma-sintering

Materials Chemistry and Physics ◽

10.1016/j.matchemphys.2003.08.009 ◽

2004 ◽

Vol 83 (1) ◽

pp. 23-28 ◽

Cited By ~ 63

Author(s):

Baorang Li ◽

Xiaohui Wang ◽

Longtu Li ◽

Hui Zhou ◽

Xingtao Liu ◽

...

Keyword(s):

Dielectric Properties ◽

Spark Plasma Sintering ◽

Fine Grained ◽

Plasma Sintering ◽

Spark Plasma

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Development of WC-Fe3Al Composites by Spark Plasma Sintering Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.881.307 ◽

2016 ◽

Vol 881 ◽

pp. 307-312

Author(s):

Luis Antonio C. Ybarra ◽

Afonso Chimanski ◽

Sergio Gama ◽

Ricardo A.G. da Silva ◽

Izabel Fernanda Machado ◽

...

Keyword(s):

Spark Plasma Sintering ◽

Zinc Stearate ◽

Sintering Process ◽

X Ray Diffraction ◽

X Ray ◽

Plasma Sintering ◽

Al Composite ◽

Spark Plasma ◽

Short Time ◽

Vibration Mill

Tungsten carbide (WC) based composites are usually produced with cobalt, but this binder has the inconvenience of shortage, unstable price and potential carcinogenicity. The objective of this study was to develop WC composite with intermetallic Fe3Al matrix. Powders of WC, iron and aluminum, with composition WC-10 wt% Fe3Al, and 0.5 wt% zinc stearate were milled in a vibration mill for 6 h and sintered in a SPS (spark plasma sintering) furnace at 1150 °C for 8 min under pressure of 30 MPa. Measured density and microstructure analysis showed that the composite had significant densification during the (low-temperature, short time) sintering, and X-ray diffraction analysis showed the formation of intermetallic Fe3Al. Analysis by Vickers indentation resulted in hardness of 11.2 GPa and fracture toughness of 24.6 MPa.m1/2, showing the feasibility of producing dense WC-Fe3Al composite with high mechanical properties using the SPS technique.

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Structure and Deformation Behavior of Ti-SiC Composites Made by Mechanical Alloying and Spark Plasma Sintering

Materials ◽

10.3390/ma12081276 ◽

2019 ◽

Vol 12 (8) ◽

pp. 1276 ◽

Cited By ~ 1

Author(s):

Dariusz Garbiec ◽

Volf Leshchynsky ◽

Alberto Colella ◽

Paolo Matteazzi ◽

Piotr Siwak

Keyword(s):

Mechanical Alloying ◽

Spark Plasma Sintering ◽

Indentation Size Effect ◽

Sintering Temperature ◽

High Energy ◽

Indentation Size ◽

X Ray ◽

Plasma Sintering ◽

Spark Plasma ◽

Energy Ball

Combining high energy ball milling and spark plasma sintering is one of the most promising technologies in materials science. The mechanical alloying process enables the production of nanostructured composite powders that can be successfully spark plasma sintered in a very short time, while preserving the nanostructure and enhancing the mechanical properties of the composite. Composites with MAX phases are among the most promising materials. In this study, Ti/SiC composite powder was produced by high energy ball milling and then consolidated by spark plasma sintering. During both processes, Ti3SiC2, TiC and Ti5Si3 phases were formed. Scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction study showed that the phase composition of the spark plasma sintered composites consists mainly of Ti3SiC2 and a mixture of TiC and Ti5Si3 phases which have a different indentation size effect. The influence of the sintering temperature on the Ti-SiC composite structure and properties is defined. The effect of the Ti3SiC2 MAX phase grain growth was found at a sintering temperature of 1400–1450 °C. The indentation size effect at the nanoscale for Ti3SiC2, TiC+Ti5Si3 and SiC-Ti phases is analyzed on the basis of the strain gradient plasticity theory and the equation constants were defined.

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Spark Plasma Sintering of Ti-4.5Al-3V-2Fe-2Mo (SP-700)

Materials Science Forum ◽

10.4028/www.scientific.net/msf.654-656.819 ◽

2010 ◽

Vol 654-656 ◽

pp. 819-822

Author(s):

Genki Kikuchi ◽

Hiroshi Izui ◽

Yuya Takahashi ◽

Shota Fujino

Keyword(s):

Spark Plasma Sintering ◽

Room Temperature ◽

Volume Fraction ◽

Titanium Boride ◽

Tensile Tests ◽

X Ray Diffraction ◽

X Ray ◽

Plasma Sintering ◽

Spark Plasma ◽

Tib2 Particles

In this study, we focused on the sintering performance of Ti-4.5Al-3V-2Mo-2Fe (SP-700) and mechanical properties of SP-700 reinforced with titanium boride (TiB/SP-700) fabricated by spark plasma sintering (SPS). TiB whiskers formed in titanium by a solid-state reaction of titanium and TiB2 particles were analyzed with scanning electron microscopy and X-ray diffraction. The TiB/SP-700 was sintered at temperatures of 1073, 1173, and 1273 K and a pressure of 70 MPa for 10, 30, and 50 min. The volume fraction of TiB ranged from 1.7 vol.% to 19.9 vol.%. Tensile tests of TiB/SP-700 were conducted at room temperature, and the effect of TiB volume fraction on the tensile properties was investigated.

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Influence of Oxygen Substoichiometry on the Dielectric Properties of BaTiO3-δNanoceramics Obtained by Spark Plasma Sintering

International Journal of Applied Ceramic Technology ◽

10.1111/ijac.12058 ◽

2013 ◽

Vol 10 ◽

pp. E122-E133 ◽

Cited By ~ 17

Author(s):

Christophe Voisin ◽

Sophie Guillemet-Fritsch ◽

Pascal Dufour ◽

Christophe Tenailleau ◽

Hyuksu Han ◽

...

Keyword(s):

Dielectric Properties ◽

Spark Plasma Sintering ◽

Plasma Sintering ◽

Spark Plasma

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Spark Plasma Sintering of Paper-Derived Ti3AlC2-Based Composites: Influence of Sintering Temperature

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1016.1790 ◽

2021 ◽

Vol 1016 ◽

pp. 1790-1796

Author(s):

Maxim Syrtanov ◽

Egor Kashkarov ◽

Tatyana Murashkina ◽

Nahum Travitzky

Keyword(s):

Phase Composition ◽

Spark Plasma Sintering ◽

Sintering Temperature ◽

Total Content ◽

X Ray Diffraction ◽

X Ray ◽

Carbide Phases ◽

Plasma Sintering ◽

Spark Plasma ◽

Scanning Electron

This paper describes the influence of sintering temperature on phase composition and microstructure of paper-derived Ti3AlC2 composites fabricated by spark plasma sintering. The composites were sintered at 100 MPa pressure in the temperature range of 1150-1350 °C. Phase composition and microstructure were analyzed by X-ray diffraction and scanning electron microscopy, respectively. The multiphase structure was observed in the sintered composites consisting of Ti3AlC2, Ti2AlC, TiC and Al2O3 phases. The decomposition of the Ti3AlC2 phase into Ti2AlC and TiC carbide phases was observed with temperature rise. The total content of Ti3AlC2 and Ti2AlC phases was reduced from 84.5 vol.% (1150 °C) to 69.5 vol.% (1350 °C). The density of composites affected by both the content of TiC phase and changes in porosity.

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