Results 131 to 140 of about 780 (184)

Densification mechanism of spark plasma sintered ZrB2 and ZrB2-SiC ceramic composites

Materials Characterization, 2021
Abstract Sintering mechanisms are investigated by determining activation energy of densification (in the temperature range of 1650 °C to 1950 °C) during spark plasma sintering of ZrB2 and SiC-reinforced ZrB2 ceramic composite. The fractured surfaces of sintered composites reveal completely dense microstructures above 1800 °C, whereas porous ...
Rubia Hassan, Kantesh Balani
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Thermal shock resistance of ZrB2 and ZrB2–30% SiC

Materials Chemistry and Physics, 2008
Abstract Thermal shock of high density (>99% relative density) zirconium diboride (ZrB2) and zirconium diboride containing 30 vol.% silicon carbide (SiC) was studied. Calculations based on thermal shock theory indicated that ZrB2–30 vol.% SiC should have greater thermal shock resistance than ZrB2 due to its higher fracture strength.
James W. Zimmermann, Greg E. Hilmas, William G. Fahrenholtz   +2 more
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Influence of chromium diboride on the oxidation resistance of ZrB2-MoSi2 and ZrB2-SiC ceramics

Journal of the European Ceramic Society, 2021
Abstract The effect of chromium diboride addition on the densification process and oxidation behavior of two ZrB2-MoSi2 and ZrB2-SiC baseline systems was studied. CrB2 was beneficial in lowering the sintering temperature owing to the tendency of its oxide to react with MoSi2 and SiC forming low-melting phases that helped the powder consolidation ...
O. Grigoriev, I. Neshpor, D. Vedel, T. Mosina, L. Silvestroni   +4 more
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Effect of the ZrB2 content on the oxygen blocking ability of ZrB2-SiC coating at 1973K

Journal of the European Ceramic Society, 2021
Abstract ZrB2-SiC coatings were prepared by spark plasma sintering method. The effect of ZrB2 content ranging from 20wt.% to 80 wt.% on the oxidation behavior of the ZrB2-SiC coatings was investigated at 1973K in air. In the initial oxidation stage (
Xuanru Ren, Hongao Chu, Keyou Wu, Anni Zhang, Menglin Huang, Can Ma, Haifeng Liu, Peizhong Feng   +7 more
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Laser modified microstructures in ZrB2, ZrB2/SiC and ZrC

Journal of the European Ceramic Society, 2010
Abstract Microstructural evolution of spark plasma sintered ZrB 2 , ZrB 2 /20 vol.% SiC (ZS20) and ZrC ultra high temperature ceramics (UHTCs) during laser heating has been investigated. Laser heating at temperatures between 2000 and 3750 °C for up to 300 s, in air or vacuum, resulted in extensive bubble and crater formation on the surfaces of 10 mm ...
D.D. Jayaseelan, H. Jackson, E. Eakins, P. Brown, W.E. Lee   +4 more
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Heat conduction mechanisms in hot pressed ZrB2 and ZrB2–SiC composites

Journal of the European Ceramic Society, 2013
Abstract Thermal diffusivity and conductivity of hot pressed ZrB 2 with different amounts of B 4 C (0–5 wt%) and ZrB 2 –SiC composites (10–30 vol% SiC) were investigated experimentally over a wide range of temperature (25–1500 °C). Both thermal diffusivity and thermal conductivity were found to decrease with increase in temperature for all the hot ...
Manish Patel, V.V. Bhanu Prasad, Vikram Jayaram   +2 more
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In situ studies of oxidation of ZrB2 and ZrB2–SiC composites at high temperatures

Journal of the European Ceramic Society, 2010
Abstract High temperature oxidation of ZrB 2 and the effect of SiC on controlling the oxidation of ZrB 2 in ZrB 2 –SiC composites were studied in situ, in air, using X-ray diffraction. Oxidation was studied by quantitatively analyzing the crystalline phase changes in the samples, both non-isothermally, as a function of temperature, up to ∼1650 °C ...
P. Sarin, P.E. Driemeyer, R.P. Haggerty, D.-K. Kim, J.L. Bell, Z.D. Apostolov, W.M. Kriven   +6 more
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Microstructure and Properties of ZrB2-Based Ceramics

Journal of Materials Processing & Manufacturing Science, 2000
Microstructure and properties of zirconium diboride based ceramics, sintered without sintering aids and with the addition of 4 wt% of nickel, are evaluated. Although the two powder compositions have been densified by hot pressing, only the presence of Ni allows the achievement of high final densities (98%), while pure ZrB2 presents a residual porosity ...
Bellosi A., Monteverde F., Fabbriche D. D., Melandri C.   +3 more
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Microstructure and shear strength of self-joined ZrB2 and ZrB2–SiC with pure Ni

Scripta Materialia, 2011
Monolithic ZrB2 ceramic and ZrB2–20 vol.% SiC composite were joined to themselves using pure nickel powder. The interfacial phenomena were observed and analyzed. The joining effects were evaluated by shear strength. Resulting from the special interfacial microstructure, the shear strength of ZrB2/Ni/ZrB2 system was as high as 59.7 ± 5.3 MPa.
Bo Yuan, Guo-Jun Zhang
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High-temperature properties of ZrB2–HfB2 and ZrB2–HfB2–SiC solid solutions

Physicochemical Mechanics of Materials
Solid (ZrxHf1–х)B2 and (ZrxHf1–х)B2–15 vol.% SiC composites were obtained by hot pressing. It was shown that the formation of homogeneous solid solution occurs at an equimolar ratio. The coreshell structure was formed in composite with 25 and 75 at.% HfB2.
D. V. Vedel, P. V. Mazur, I. V. Kozak, A. Ye. Osipov, M. P. Brodnikovskyi   +4 more
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