Effects of spark plasma sintering temperature on densification, hardness and thermal conductivity of titanium carbide

Aluminum nitride-boron nitride (AlN/BN) composite ceramics were prepared by spark plasma sintering (SPS). The sintering behaviors of AlN/BN composites with 5~15% volume fraction of BN were studied. The influences of BN content, as well as the sintering temperature on the density, microstructure, mechanical strength, thermal conductivity and machinability of the composites were also investigated. The results showed that the full densification of AlN/BN composite ceramics could be realized by SPS technique at the temperature no higher than 1800°C for 3 minutes. The thermal conductivity of AlN/BN composites is in the range of 66~79W/mK, and AlN/BN composites can be cut or drilled by carbides or even steel tools when BN content is 15% volume fraction. The mechanical strength of AlN/BN composites is about 330MPa and is not remarkably affected by the addition of BN. The improvement of mechanical properties of AlN/BN composite ceramics is due to the fine and homogenous microstructure developed in the SPS process.

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Effect of Dopant on N-Type Bi2Te2.7Se0.3 Thermoelectric Materials Fabricated by Spark Plasma Sintering

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.544 ◽

2008 ◽

Vol 368-372 ◽

pp. 544-546

Author(s):

Dong Choul Cho ◽

Jae Seol Lee ◽

Chul Ho Lim ◽

Chi Hwan Lee

Keyword(s):

Thermal Conductivity ◽

Spark Plasma Sintering ◽

Sintering Temperature ◽

Sintered Sample ◽

Dopant Content ◽

Plasma Sintering ◽

Spark Plasma ◽

P Type ◽

Type Conduction

The n-type Bi2Te2.7Se0.3 compounds were fabricated to investigate the characterization of spark plasma sintering with various SbI3 dopant contents. The Bi2Te2.7Se0.3 compounds with SbI3 dopant content is exhibited n-type conduction characterization, but the Bi2Te2.7Se0.3 compounds without SbI3 dopant content is exhibited p-type conduction characterization. The maximum Seebeck coeficient represented with 0.05wt.% SbI3 dopant content. The Seebeck coefficient of the sintered sample with increasing sintering temperature is increased from -158 to -182 μV/K. The electrical resistivity and thermal conductivity with 0.05wt.% SbI3 dopant content were 1.0 m and 1.33 W/mK, respectively.

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Fabrication and Thermoelectric Properties of N-Type Bi2Te3 Based Compounds by Spark Plasma Sintering

Materials Science Forum ◽

10.4028/www.scientific.net/msf.486-487.253 ◽

2005 ◽

Vol 486-487 ◽

pp. 253-256 ◽

Cited By ~ 1

Author(s):

D.M. Lee ◽

Cheol Ho Lim ◽

Dong Choul Cho ◽

Seung Y. Shin ◽

Won Seung Cho

Keyword(s):

Thermal Conductivity ◽

Electrical Resistivity ◽

Spark Plasma Sintering ◽

Thermoelectric Properties ◽

Figure Of Merit ◽

Bending Strength ◽

Sintering Temperature ◽

Powder Size ◽

Plasma Sintering ◽

Spark Plasma

N-type Bi2Te3 based thermoelectric compound was prepared by spark plasma sintering with a temperature range of 340~460°C and powder size of ~75㎛, 76~150㎛, 151~250㎛. Thermoelectric properties of the compound were measured as a function of the sintering temperature and powder size. With increasing sintering temperature, the electrical resistivity and thermal conductivity of the compound greatly changed because of the increase in relative density. The Seebeck coefficient and electrical resistivity were varied largely with increasing powder size. Therefore, the compound sintered at 460°C, with the powder of ~75㎛, showed a figure of merit of 2.44 x 10-3/K. Also, the bending strength was 75MPa.

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Preparation and Properties of ZrB2-Cu Composites by Spark Plasma Sintering

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.512-515.739 ◽

2012 ◽

Vol 512-515 ◽

pp. 739-743 ◽

Cited By ~ 7

Author(s):

S.Z. Zhu ◽

D.L. Gong ◽

Z. Fang ◽

Q. Xu

Keyword(s):

Mechanical Properties ◽

Thermal Conductivity ◽

Relative Density ◽

Spark Plasma Sintering ◽

Volume Fraction ◽

Sintering Temperature ◽

High Electrical Conductivity ◽

Particulate Reinforcement ◽

Plasma Sintering ◽

Spark Plasma

For high thermal conductivity and high electrical conductivity, copper is a good electrode material. The wearing resistance and spark resistance of Cu can be improved with the addition of ZrB2. ZrB2-Cu composites with high Cu volume fraction was successfully prepared by spark plasma sintering (SPS) process in this paper. The microstructure and properties of the sintered samples were characterized. The effect of the sintering temperature and the ZrB2 content in composites on the relative density and properties of the composites were investigated. The results show that the relative density and mechanical properties increase with the sintering temperature increasing. The optimum sintering temperature is 900 °C for 10wt.% ZrB2-Cu, 1000 °C for 20wt.% ZrB2-Cu and 1050 °C for 30wt.% ZrB2-Cu. With the ZrB2 content in composites increasing from 10wt.% to 30 wt.%, the electrical resistivity increases from 2.25×10-6 Ω.cm to 8.82×10-6 Ω.cm, the flexural strength decreases from to 539.1 MPa to 482.2 MPa and the fracture toughness decreases from to 15 MPa.m 1/2 to 9 MPa.m 1/2. The hardness (HV) of ZrB2-Cu composites is significantly enhanced by the ZrB2 particulate reinforcement, increasing from 1410 MPa for 10 wt.% ZrB2 to 2480 MPa for 30wt.% ZrB2.

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Effects of theTiB2-SiC Volume Ratio and Spark Plasma Sintering Temperature on the Properties and Microstructure of TiB2-BN-SiC Composite Ceramics

Crystals ◽

10.3390/cryst12010029 ◽

2021 ◽

Vol 12 (1) ◽

pp. 29

Author(s):

Shi Tian ◽

Zelin Liao ◽

Wenchao Guo ◽

Qianglong He ◽

Heng Wang ◽

...

Keyword(s):

Thermal Conductivity ◽

Thermal Expansion ◽

High Temperature ◽

Spark Plasma Sintering ◽

Sintering Temperature ◽

Volume Ratio ◽

Expansion Rate ◽

Composite Ceramics ◽

Plasma Sintering ◽

Spark Plasma

TiB2-BN composite ceramics combine excellent electrical conductivity, thermal shock resistance, high-temperature resistance, corrosion resistance, and easy processing of TiB2 and BN. However, in practical applications, their high-temperature oxidation resistance is poor and the resistivity distribution is uneven and changes substantially with temperature. A TiB2-BN-SiC composite ceramic with stable and controllable resistivity was prepared by introducing SiC into the TiB2-BN composite ceramics. In this work, spark plasma sintering (SPS) technology was used to prepare TiB2-BN-SiC composite ceramics with various TiB2-SiC ratios and sintering temperatures. The samples were tested by XRD, SEM, and thermal and mechanical analysis. The results show that as the volume ratio of TiB2-SiC was increased from 3:1 to 12:1, the resistivity of the sample decreased from 8053.3 to 4923.3 μΩ·cm, the thermal conductivity increased from 24.89 to 34.15 W/(m k), and the thermal expansion rate increased from 7.49 (10−6/K) to 10.81 (10−6/K). As the sintering temperature was increased from 1650 to 1950 °C, the density of the sample increased, the mechanical properties were slightly improved, and the resistivity, thermal expansion rate, and thermal conductivity changed substantially. The volume ratio and sintering temperature are the key factors that control the resistivity and thermal characteristics of TiB2-SiC-BN composite ceramics, and the in situ from liquid phases of FeB and FeO also promotes the sintering of the TiB2-BN-SiC ceramics.

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Microstructure and Thermoelectric Properties of P-Type Bi0.5Sb1.5Te3 Compounds Prepared by Spark Plasma Sintering

Materials Science Forum ◽

10.4028/www.scientific.net/msf.510-511.1122 ◽

2006 ◽

Vol 510-511 ◽

pp. 1122-1125

Author(s):

Won Seung Cho ◽

Dong Choul Cho ◽

Cheol Ho Lim ◽

C.H. Lee ◽

Woon Suk Hwang ◽

...

Keyword(s):

Thermal Conductivity ◽

Electrical Resistivity ◽

Seebeck Coefficient ◽

Spark Plasma Sintering ◽

Hydrogen Reduction ◽

Sintering Temperature ◽

Reduction Process ◽

Plasma Sintering ◽

Spark Plasma ◽

P Type

The microstructure and thermoelectrical properties of the 4wt% Te doped p-type Bi0.5Sb1.5Te3 compounds, fabricated by using spark plasma sintering in the temperature ranging from 250°C to 350°C, were characterized. The density of the sintered compounds was increased to 99.2% of theoretical density by carrying out the consolidation at 350oC for 2 min. The Seebeck coefficient, thermal conductivity and electrical resistivity were dependent on hydrogen reduction process and sintering temperature. The Seebeck coefficient increased with reduction process while the electrical resisitivity significantly decreased. Also, the electrical resistivity decreased and thermal conductivity increased with sintering temperature. The results suggest that the carrier density and mobility vary with reduction process and sintering temperature. The highest figure of merit of 3.5×10-3/K was obtained for the compounds spark plasma sintered at 350°C for 2 min by using the hydrogen-reduced powders.

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AlN/CNT Composites Ceramics by Spark Plasma Sintering

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.602-603.570 ◽

2014 ◽

Vol 602-603 ◽

pp. 570-573

Author(s):

Hai Long Liang ◽

Chun Peng Wang ◽

Yan Li Huo ◽

Chuan Qi Hu ◽

Xiao Ting Huang ◽

...

Keyword(s):

Thermal Conductivity ◽

High Temperature ◽

Spark Plasma Sintering ◽

Imaginary Part ◽

Loss Factor ◽

Sintering Temperature ◽

Sintering Process ◽

Composite Ceramics ◽

Plasma Sintering ◽

Spark Plasma

Highly dense AlN/CNT composite ceramics with 1-10% volume fractions of CNT were fabricated by spark plasma sintered (SPS) at 1400°C-1700°C. The results indicated that origination diameter of AlN had a great effect on microstructure and thermal conductivity. In details, for the system with AlN origination diameter of nanosized, the tubular structure of CNT has not been destructed, but when micro-sized AlN powder was adopted, the structure of CNT showed unstable at high temperature. Even though the degradation with incorporation of CNT into AlN, thermal conductivity of sintered AlN/CNT composites ceramics was evidently improved by adjusting content of additive Y2O3and the sintering process. Both the real part and imaginary part of the composites of Ka-Band (26.540.0 GHz) increase with the increase of CNT content, in which the increase of imaginary part is more than that of real part, resulting in an increase of loss factor. The AlN/ CNT thermal conductivity composites with appropriate CNT content and sintering temperature possess good dielectric dissipation and thermal conductivity.

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Effect of spark plasma sintering temperature on structure and phase composition of Ti-Al-Nb-based alloys

Materials Testing ◽

10.3139/120.111107 ◽

2017 ◽

Vol 59 (11-12) ◽

pp. 1033-1036 ◽

Cited By ~ 1

Author(s):

Sherzod Kurbanbekov ◽

Mazhyn Skakov ◽

Viktor Baklanov ◽

Batyrzhan Karakozov

Keyword(s):

Phase Composition ◽

Spark Plasma Sintering ◽

Sintering Temperature ◽

Plasma Sintering ◽

Spark Plasma

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Densification and Thermal Conductivity of Y2O3-Doped AlN Ceramics by Spark Plasma Sintering

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.352.227 ◽

2007 ◽

Vol 352 ◽

pp. 227-231 ◽

Cited By ~ 2

Author(s):

Qiang Shen ◽

Z.D. Wei ◽

Mei Juan Li ◽

Lian Meng Zhang

Keyword(s):

Thermal Conductivity ◽

Grain Boundaries ◽

Spark Plasma Sintering ◽

Particle Surface ◽

Boundary Phase ◽

Homogeneous Microstructure ◽

Densification Mechanism ◽

Sintering Additive ◽

Plasma Sintering ◽

Spark Plasma

AlN ceramics doped with yttrium oxide (Y2O3) as the sintering additive were prepared via the spark plasma sintering (SPS) technique. The sintering behaviors and densification mechanism were mainly investigated. The results showed that Y2O3 addition could promote the AlN densification. Y2O3-doped AlN samples could be densified at low temperatures of 1600-1700oC in 20-25 minutes. The AlN samples were characterized with homogeneous microstructure. The Y-Al-O compounds were created on the grain boundaries due to the reactions between Y2O3 and Al2O3 on AlN particle surface. With increasing the sintering temperature, AlN grains grew up, and the location of grain boundaries as well as the phase compositions changed. The Y/Al ratio in the aluminates increased, from Y3Al5O12 to YAlO3 and to Y4Al2O9. High-density, the growth of AlN grains and the homogenous dispersion of boundary phase were helpful to improve the thermal conductivity of AlN ceramics. The thermal conductivity of 122Wm-1K-1 for the 4.0 mass%Y2O3-doped AlN sample was reached.

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