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http://dx.doi.org/10.6111/JKCGCT.2021.31.5.197

Crystal structure and microstructure of Z-type hexaferrite (Ba, La)Co2Fe24O41 by molten salt synthesis  

Lee, Do Hyeok (School of Materials Science and Engineering, Gyeongsang National University)
Kwon, Chae-Yeon (School of Materials Science and Engineering, Gyeongsang National University)
Moon, Kyoung-Seok (School of Materials Science and Engineering, Gyeongsang National University)
Publication Information
Journal of the Korean Crystal Growth and Crystal Technology / v.31, no.5, 2021 , pp. 197-202 More about this Journal
Abstract
Synthesis of Z-type hexaferrite Ba3Co2Fe24O41 (Ba3Z) and Ba1.5La1.5Co2Fe24O41 (Ba1.5La1.5Z) powders were tried using molten salt synthesis after primary calcination. Ba3Z calcined at 1000℃ was formed with both M-type and Y-type hexaferrite, and then Z-type was obtained when sintered with molten salt at 1150℃ and 1200℃. In the case of Ba1.5La1.5Z calcined at 1000℃, however, M-type hexaferrite, CoFe2O4 (Spinel phase), and LaFeO3 were synthesized. As a result, Z-type hexaferrite was not synthesized after sintering with molten salt. In addition, the aspect ratio of the particles decreased as the sintering temperature increased with molten salt synthesis. To obtain a single-phase Ba1.5La1.5Z with a high aspect ratio, it is expected the raw materials have to calcine below the temperature of a spinel phase formation before sintering with molten salt.
Keywords
Hexaferrite; Molten salt; Crystal structure; Microstructure;
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