Synthesis of B4C/ZrB2 Composite Powders via Boron Carbide Reduction for Ceramic Fabrication

• Published in: Inorganic materials Vol. 58; no. 9; pp. 912 - 921
• Main Authors: Gudyma, T. S., Krutskii, Yu. L., Maksimovskii, E. A., Ukhina, A. V., Aparnev, A. I., Smirnov, A. I., Uvarov, N. F.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.09.2022; Springer Nature B.V
• Subjects: Boron; Boron carbide; Carbon fibers; Ceramic powders; Chemistry; Chemistry and Materials Science; Composite materials; Composition; Inclusions; Industrial Chemistry/Chemical Engineering; Inorganic Chemistry; Materials Science; Mixtures; Nanofibers; Oxidation; Photomicrographs; Reducing agents; Refractory materials; Synthesis; Thermal stability; Zirconium carbide; Zirconium compounds; Zirconium oxides; ceramic; boron carbide reduction; zirconium diboride; modifying additive; boron carbide
• ISSN: 0020-1685; 1608-3172
• DOI: 10.1134/S0020168522090059

— In this paper, we report the preparation of a B 4 C/ZrB 2 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 % ZrB 2 . 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 B 4 C and ZrB 2 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 % ZrB 2 had a uniform modifying additive distribution over the B 4 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 m 2 /g. The zirconium diboride particles were uniformly distributed over the boron carbide matrix. Increasing the ZrB 2 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.