Sintering of boron carbide and boron carbide-silicon carbide two-phase materials and their properties
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. Pressureless...
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Published in | Journal of nuclear materials Vol. 152; no. 2; pp. 154 - 162 |
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Main Author | |
Format | Journal Article |
Language | English |
Published |
Elsevier B.V
01.05.1988
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Online Access | Get full text |
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Summary: | 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. Pressureless sintering using metallic, inorganic, B + C, additives is not successful, since, despite having a high density, impurities remain present. Pressureless sintering of boron carbide (or silicon carbide composite) using free carbon addition, produced by in-situ pyrolysis of a Novolaque-type phenol-formaldehyde resin (≈ 9 wt%), is now possible in industry. A promising new method is the use of organic precursors, e.g. polycarbosilane with a small amount of phenolic resin, giving CSi and C by in-situ pyrolysis; the resulting boron carbide ceramics have high density (> 92%) and contain no free carbon and a small amount of SiC (≈ 5 wt%). The mechanical properties of sintered B
4C are close to those of hot-pressed; the SiC dispersion in a B
4C matrix has no toughening effect. |
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Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 |
ISSN: | 0022-3115 1873-4820 |
DOI: | 10.1016/0022-3115(88)90321-2 |