Journal of the Korean Ceramic Society (한국세라믹학회지)

The Korean Ceramic Society (한국세라믹학회)
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Crystal Structures of Ba-ferrites Synthesize by Coprecipitation-Oxidation Method

공침-산화법으로 합성된 바륨페라이트의 결정구조

  • Published : 1997.10.01
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Abstract

Barium ferrites (BaFe12O19) were synthesized at the various temperature by the coprecipitation-oxidation method. X-ray diffraction Rietveld analysis for barium ferrites were performed, their microstructures were observed and their magnetic properties were measured, in order to analyze the crystal structures and determine the optimal temperature of heat-treatment. The barium ferrite, its average particle size 80 nm, was formed at 600℃ through the hematite (α-Fe2O3), but the site occupations of the Fe's in tetrahedral and bipyramidal sites and of the Ba relatively low. Increasing the heating temperature, these occupations and the magnetization increased, and the crystal c-axis decreased. These changes were very small at the heat treatment of above 800℃, but the particles were rapidly grown. It is suggested that the optimal temperature of heat-treatment is 800℃, at which temperature crystal structure is relatively stable and the particles hardly ever grow.

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