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Metallography of boron carbide
Metallography, 1976A method of preparing B/sub 4/C for metallographic examination is described. The specimen is first cut with a diamond saw to produce a reasonably flat surface in order to reduce the grinding time. It is then mounted in a plastic material with pieces of a hard material (e.g., alumina) disposed around it to preserve flatness during grinding and polishing
B. Champagne, M. Beauvy, R. Angers
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Journal of Nuclear Materials, 1988
Boron carbide is a high-technological ceramic material (it is used for lightweight armor, neutron absorbers, wear pieces, etc.). Hot pressing (2200°C, 40 MPa, Ar atmosphere) and recently high isostatic pressing, are the best known ways for industrial preparation of boron carbide items.
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Boron carbide is a high-technological ceramic material (it is used for lightweight armor, neutron absorbers, wear pieces, etc.). Hot pressing (2200°C, 40 MPa, Ar atmosphere) and recently high isostatic pressing, are the best known ways for industrial preparation of boron carbide items.
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An Investigation of Boron Carbide
Journal of Applied Physics, 1953Mixtures of boron and carbon were heated at approximately 2000°C; the reaction products have been studied by x-ray diffraction and by density and electrical measurements. The existance of a wide range of homogeneity of ``boron carbide'' has been established. No evidence of compound formation corresponding to B4C could be detected.
Frank W. Glaser +2 more
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Russian Journal of General Chemistry, 2019
The issues of the composition-structure relationship of boron carbide are discussed. A new hypothesis based on the presence of channels with a diameter of 2.7–2.9 A in crystals, into which C or B atoms can be intruded, has been proposed. The intrusion has been confirmed by the data of quantum-chemical simulation using VASP program.
S. V. Konovalikhin +3 more
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The issues of the composition-structure relationship of boron carbide are discussed. A new hypothesis based on the presence of channels with a diameter of 2.7–2.9 A in crystals, into which C or B atoms can be intruded, has been proposed. The intrusion has been confirmed by the data of quantum-chemical simulation using VASP program.
S. V. Konovalikhin +3 more
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Photoluminescence of boron carbide
Journal of Solid State Chemistry, 2004Abstract The excitation of B4.3C with an Ar-laser ( ℏω=2.4 eV ) yields a photoluminescence spectrum between about 1.56 and 1.58 eV with its main maximum at 1.563 eV and a weaker maximum at 1.572 eV. It is attributed to the indirect-allowed recombination of free excitons.
R. Schmechel +3 more
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Preparation of Boron from Boron Carbide
Journal of The Electrochemical Society, 1960A process for the preparation of elemental boron from boron carbide is presented. Included is evidence which shows that the process is one of anodic transfer. Boron of at least 99.8% purity can be made directly from technical-grade materials. Purity is a function of electrolysis voltages and boron carbide purity.
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Journal of the Less Common Metals, 1986
Abstract The common X-ray diffractometer powder techniques used to determine the amount of free graphite in boron carbide usually do not include any corrections for grain orientation. It has also been shown that the preparation of the samples by grinding and the addition of plate-like graphite powder induces a preferential orientation of the grains ...
M. Bougoin +3 more
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Abstract The common X-ray diffractometer powder techniques used to determine the amount of free graphite in boron carbide usually do not include any corrections for grain orientation. It has also been shown that the preparation of the samples by grinding and the addition of plate-like graphite powder induces a preferential orientation of the grains ...
M. Bougoin +3 more
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The oxidation of boron carbide
Soviet Powder Metallurgy and Metal Ceramics, 19641. A study was made of the oxidation of boron carbide and carbon black by different oxidizers: mixtures of sulfuric acid with potassium bichromate, sulfuric acid with potassium permanganate, sulfuric, nitric, and perchloric acids with potassium bichromate, etc.
T. N. Nazarchuk, L. N. Mekhanoshina
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2020
For the first time, free boron was obtained in 1808 by Louis Joseph Gay-Lussac and Louis Jacques Tenard by heating B2O3 boron oxide with metallic potassium.
Mikhail Gasik +2 more
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For the first time, free boron was obtained in 1808 by Louis Joseph Gay-Lussac and Louis Jacques Tenard by heating B2O3 boron oxide with metallic potassium.
Mikhail Gasik +2 more
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Boron Carbide/Boron Carbide-Carbon Nanofibers Laminates with Weak Interfaces
2010Three layered B4C/B4C-Cnanofibers laminates have been produced using a hot pressing technique. The laminates were designed with thick (~2.6 mm) outer layers of B4C and a thin (~90 µm) center layer of B4C-70 wt% Cnanofibers. It was found that low tensile thermal residual stress develops in the thick B4C outer layers.
Nina Orlovskaya +7 more
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