1. Synthesis of B4C/ZrB2 Composite Powders via Boron Carbide Reduction for Ceramic Fabrication.
- Author
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Gudyma, T. S., Krutskii, Yu. L., Maksimovskii, E. A., Ukhina, A. V., Aparnev, A. I., Smirnov, A. I., and Uvarov, N. F.
- Subjects
BORON carbides ,POWDERS ,CERAMICS ,COMPOSITE materials ,CERAMIC powders ,ZIRCONIUM oxide ,ZIRCONIUM carbide - Abstract
In this paper, we report the preparation of a B
4 C/ZrB2 composite powder material via boron carbide reduction of zirconium oxide in the presence of carbon nanofiber as a carbon reducing agent. The material was synthesized in the temperature range 1200–1900°C in 20 min. The optimal synthesis temperature was 1650°C, independent of the starting-mixture composition. We have studied characteristics of the composite powders containing 10–30 mol % ZrB2 . The 50% particle size of the composite powders with the compositions studied does not exceed 9.5 μm. The powders consist of aggregated particles of the B4 C and ZrB2 phases up to 10 and 40 μm in size, respectively. Visual analysis of micrographs of the powders showed that the mixtures containing 20–30 mol % ZrB2 had a uniform modifying additive distribution over the B4 C particles and that the content of large and medium inclusions did not exceed 15 vol %. The specific surface area of the samples ranged from 1.3 to 2.1 m2 /g. The zirconium diboride particles were uniformly distributed over the boron carbide matrix. Increasing the ZrB2 content of the composite powder material from 10 to 30 mol % improved the thermal stability of the material in an oxidizing medium. The composite material is potentially attractive for ceramic fabrication. [ABSTRACT FROM AUTHOR]- Published
- 2022
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