Results 201 to 210 of about 12,064 (254)

THE NIOBIUM—NIOBIUM CARBIDE SYSTEM¹

The Journal of Physical Chemistry, 1960
The solid pontion of the Nb--NbC phase diagram was determined. The following characteristic temperatures were measured: a eutectic temperature between NbC/sub 0.08/ and NbC/sub 0.39/ of 2335 plus or minus 20 deg C, a peritectic temperature between NbC/sub 0.52/ and NbC/sub 0.56/ of 3090 deg 50 deg C and a melting point maximum at about NbC/sub 0.86/ of
E. K. Storms, N. H. Krikorian
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Fabrication of niobium carbide coating on niobium by interstitial carburization

International Journal of Refractory Metals and Hard Materials, 2020
Abstract Ceramic coatings on niobium substrates are fabricated by hot-pressing the niobium with cast iron at 1100 °C. The interstitial carbon atoms diffuse into the niobium, and NbC and Nb2C precipitate in the surface, forming a ceramic coating. The total volume fraction of the ceramic phases in the coating reaches 92%, and the grain size is in the ...
Ziyuan Zhao, Pengfei Hui, Fuyuan Liu, Yunhua Xu, Lisheng Zhong, Mingxuan Zhao   +5 more
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Sintering behavior of niobium carbide

Soviet Powder Metallurgy and Metal Ceramics, 1974
1. The kinetics of the sintering of niobium carbide is largely determined by the presence in the latter of iron, which is picked up during milling in units with steel balls. Activated sintering was found to be exhibited by powder containing, in the starting condition, as little as 0.3 wt.% of iron. No upper limit of the activating action of iron has
V. S. Kindysheva, P. S. Kislyi
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Optical and electrical properties of niobium carbide

Physical Review B, 1987
The optical and electrical properties were measured for single crystals of ${\mathrm{NbC}}_{\mathrm{x}}$ for x=0.98, 0.87, and 0.76, and for one hot-isostatically-pressed sample of ${\mathrm{NbC}}_{0.88}$. Specular reflectance was measured between 0.025 and 11 eV, and ellipsometry measurements were made at 1.96 eV.
, Allison, , Modine, , French
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Vaporization behavior of niobium carbide

Vacuum, 1962
The vaporization behavior of niobium carbide was studied over the temperature range from 2260° to 2940°K utilizing the Langmuir method. NbC was observed to lose carbon preferentially down to a composition of NbC0.75, at which composition the vaporization proceeds congruently at a temperature of 2940°K.
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Crystal growth of niobium nitride and niobium carbide nitride

Journal of Crystal Growth, 1978
Abstract Single crystals of niobium carbide nitride were obtained by zone melting growth in ambient nitrogen gas pressures of up to 9.0 MPa. Single crystals of δ-NbN or γ-NbN could not be obtained by this method, but single crystals of γ-NbN were obtained by annealing of NbN in nitrogen gas pressures of up to 2.0 MPa.
A.Nørlund Christensen, C. Rusche
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Activated sintering of niobium carbide

Soviet Powder Metallurgy and Metal Ceramics, 1963
1. A process has been proposed for the activated sintering of niobium carbide with additions of Fe and CoCl2; other conditions being equal, this process permits a three-fold increase in the packing of sintered components. 2. We have discussed processes occurring during activated sintering, on the basis of Dawihl's ideas [4] on packing ...
P. S. Kislyi, A. D. Panasyuk, G. V. Samsonov   +2 more
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Gas evolution from zirconium carbide, niobium carbide, and tantalum carbide powders

Soviet Powder Metallurgy and Metal Ceramics, 1986
This work was undertaken with the aim of determining the gas contents of zirconium carbide, niobium carbide, and tantalum carbide powders as functions of their processing history. A high-vacuum, high-temperature apparatus was used, connected to an oilless evacuation system and instruments for the mass-spectrometric measurement of amounts and ...
A. V. Makeev, V. V. Khromonozhkin, A. S. Maskaev, V. G. Vil'chinskii   +3 more
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ChemInform Abstract: Synthesis of Niobium Carbide from Niobium Oxide Aerogels.

ChemInform, 1995
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
V. L. S. TEIXEIRA DA SILVA, E. I. KO, M. SCHMAL, S. T. OYAMA   +3 more
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Sintering of alumina-niobium carbide composite

International Journal of Refractory Metals and Hard Materials, 1998
Abstract Several studies have been focused on particulate-dispersed Al 2 O 3 composites in order to improve both room and high temperature mechanical properties and wear resistance. In the present work Al 2 O 3 -NbC composites have been pressureless sintered and their microstructures analysed as a function of NbC and Y 2 O 3 concentration, the ...
Rosa M.R. Pasotti, Ana Helena A. Bressiani, Jose´C. Bressiani   +2 more
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