Results 131 to 140 of about 1,434 (185)
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Nanostructured Materials, 1997
Nanocomposites Fe-85 vol.% Fe3C were prepared by mechanosynthesis (MS) of elemental Fe and graphite powders. The crystallite size in the MS powder was about 7 nm for Fe3C and about 8 nm for Fe. These powders were densified by a field assisted sintering process.
T. J. GOODWIN +3 more
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Nanocomposites Fe-85 vol.% Fe3C were prepared by mechanosynthesis (MS) of elemental Fe and graphite powders. The crystallite size in the MS powder was about 7 nm for Fe3C and about 8 nm for Fe. These powders were densified by a field assisted sintering process.
T. J. GOODWIN +3 more
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Nature, 1965
SEVERAL methods for the preparation of the carbides of iron have been reported in the literature. In order to obtain a satisfactory product it may be necessary to use a relatively high temperature1, or long periods of reaction during which reaction conditions must be controlled within narrow limits for several weeks2,3.
J. FREEL, A. K. GALWEY
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SEVERAL methods for the preparation of the carbides of iron have been reported in the literature. In order to obtain a satisfactory product it may be necessary to use a relatively high temperature1, or long periods of reaction during which reaction conditions must be controlled within narrow limits for several weeks2,3.
J. FREEL, A. K. GALWEY
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Corrosion Science, 1974
Abstract The progressive changes in texture which occur during the oxidation of two different preparations of cementite (A and B) have been investigated by electron microscopy. Changes in surface texture observed during the reaction of cementite A with gaseous oxygen were ascribed to the initial formation of a coherent barrier layer of Fe3O4, the ...
A.K. Galwey +3 more
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Abstract The progressive changes in texture which occur during the oxidation of two different preparations of cementite (A and B) have been investigated by electron microscopy. Changes in surface texture observed during the reaction of cementite A with gaseous oxygen were ascribed to the initial formation of a coherent barrier layer of Fe3O4, the ...
A.K. Galwey +3 more
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Free Energy of Formation of Cementite and the Solubility of Cementite in Austenite
JOM, 1951The solubility of cementite in austenite is computed by thermodynamic methods from the observed solubility of graphite. It is found that the solubility of cementite is greater than that of graphite in the entire austenite temperature range. Thus the prior discrepancy between this portion of the phase diagram and the observed metastability of cementite ...
L. S. Darken, R. W. Gurry
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The Philosophical Magazine: A Journal of Theoretical Experimental and Applied Physics, 1968
Abstract Small angle tilt boundaries consisting of uniformly spaced edge dislocations were observed in cementite extracted from an annealed steel. The Burgers vector of the dislocations was identified as [0b0] from their average spacing and the tilt angle between both grains. The [0b0] type dislocation was related with two displacement vectors required
A. Koréeda, K. Shimizu
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Abstract Small angle tilt boundaries consisting of uniformly spaced edge dislocations were observed in cementite extracted from an annealed steel. The Burgers vector of the dislocations was identified as [0b0] from their average spacing and the tilt angle between both grains. The [0b0] type dislocation was related with two displacement vectors required
A. Koréeda, K. Shimizu
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Atomic structure of the austenite-cementite interface of proeutectoid cementite plates
Philosophical Magazine A, 1999Abstract In a previous investigation, the atomic habit plane (or terrace plane) of proeutectoid cementite plates in austenite was deduced to be (113)A‖(101)c (where the subscript A indicates austenite and the subscript C cementite), based on conventional transmission electron microscopy and computer-aided atom matching studies.
J. M. Howe, G. Spanos
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Materials Science and Technology, 1993
Abstract It is proposed that cementite owes its stability, relative to other iron carbides, to its crystal structure, which enables its carbon atoms to form extra covalent bonds with iron atom neighbours. An analysis based on tight binding theory suggests that cementite has an advantage of nearly 0·5 eV per Fe3C unit over an alternative Fe3C carbide ...
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Abstract It is proposed that cementite owes its stability, relative to other iron carbides, to its crystal structure, which enables its carbon atoms to form extra covalent bonds with iron atom neighbours. An analysis based on tight binding theory suggests that cementite has an advantage of nearly 0·5 eV per Fe3C unit over an alternative Fe3C carbide ...
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On the Mössbauer study of cementite
Physics Letters, 1966Abstract Mossbauer study on cast iron and two kinds of steels show two modifications of cementite, -one ferromagnetic and the other paramagnetic (at room temperature). The two forms were extracted as pure phases by HCl and studied.
M. Ron +3 more
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Transformation of cementite into austenite
Metal Science and Heat Treatment, 19821. Austenitization of white iron primary cementite crystals in contact with ferrite commences at the interphase boundary. Austenite is formed as a result of withdrawal of carbon atoms from cementite into ferrite. 2. Grains of austenite phase forming in cementite create lamellar clusters oriented along the direction of cementite crystal ...
V. M. Ershov, L. S. Nekrasova
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Journal of Materials Science, 1983
The hot hardness was measured on the (010) plane of primary cementite in unidirectionally solidified iron-carbon, iron-carbon-chromium, and iron-carbon-boron alloys at temperatures up to 973 K, using a hot hardness tester equipped with an indenterheating system.
Akio Kagawa, Taira Okamoto
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The hot hardness was measured on the (010) plane of primary cementite in unidirectionally solidified iron-carbon, iron-carbon-chromium, and iron-carbon-boron alloys at temperatures up to 973 K, using a hot hardness tester equipped with an indenterheating system.
Akio Kagawa, Taira Okamoto
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