Low temperature-rapid preparation of HfB<sub>2</sub>–SiC powders by microwave/molten salt assisted boro/carbothermal reduction

نویسندگان

چکیده

Phase pure HfB2–SiC powders were efficiently synthesized via microwave/molten salt assisted boro/carbothermal reduction (MMS-BCTR) method by using HfO2, SiO2, activated carbon and B4C as raw materials, NaCl–KCl a molten medium. The effects of mass ratio to reactant (ms/mr), holding period, reaction temperature content on the phase composition microstructure investigated. results showed that optimal molar HfO2/SiO2/B4C/C was 3.0:1.0:3.2:4.0, ms/mr 2.0, period respectively 1250 °C 20 min. Rod-shaped HfB2 irregular SiC particles uniformly distributed in products, former with length 0.5 µm diameter 300 nm exhibited single-crystal structure preferred growth along [100] direction, while latter had particle size about nm.

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ژورنال

عنوان ژورنال: Journal of the Ceramic Society of Japan

سال: 2021

ISSN: ['1882-0743', '1348-6535']

DOI: https://doi.org/10.2109/jcersj2.21006