Barium ferrite
Structural formula | |||||||||||||||||||
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General | |||||||||||||||||||
Surname | Barium ferrite | ||||||||||||||||||
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Molecular formula | BaFe 12 O 19 | ||||||||||||||||||
Brief description |
black solid |
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properties | |||||||||||||||||||
Molar mass | 1111.46 g mol −1 | ||||||||||||||||||
Physical state |
firmly |
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density |
5.40 g cm −3 |
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Melting point |
> 1315 ° C |
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solubility |
practically insoluble in water (<0.002 mg l −1 at 20 ° C) |
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safety instructions | |||||||||||||||||||
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As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . |
Barium ferrite is an inorganic chemical compound of barium from the group of ferrites .
Occurrence
Barium ferrite occurs naturally in the form of the mineral barioferrite .
Extraction and presentation
Barium ferrite can be obtained by reacting barium carbonate with iron (III) oxide at 1200 to 1350 ° C or by reacting a solution of barium hydroxide with iron (III) hydroxide in a sodium hydroxide solution .
properties
Barium ferrite is a black solid that is practically insoluble in water. The connection is ferrimagnetic with a Curie temperature of 450 ° C. It has a hexagonal crystal structure with the space group P 6 3 / mmc (space group no. 194) . The structure is made up of cubic and hexagonal close packing layers with the sequence BAB'ABOAO'AO in the direction of the c-axis.
use
Barium ferrite is used in speaker permanent magnets and in magnetic tapes. It is also used for radar absorbing coatings.
Individual evidence
- ↑ a b c d e f g h Entry on barium ferrite in the GESTIS substance database of the IFA , accessed on February 16, 2019(JavaScript required) .
- ↑ MN Murashko, NV Chukanov et al. a .: Barioferrite BaFe12O19: A new mineral species of the magnetoplumbite group from the Haturim Formation in Israel. In: Geology of Ore Deposits. 53, 2011, p. 558, doi : 10.1134 / S1075701511070142 .
- ^ Gunter Buxbaum: Industrial Inorganic Pigments . John Wiley & Sons, 2008, ISBN 3-527-61210-6 , pp. 189 ( limited preview in Google Book search).
- ↑ Hans-Jürgen Bargel, Hermann Hilbrans, Günter Schulze, Karl-Heinz Hübner, Oswald Krüger: Material science . Springer-Verlag, 2013, ISBN 978-3-662-10903-8 , pp. 317 ( limited preview in Google Book search).
- ↑ WD Townes, JH Fang, AJ Perrotta: The crystal structure and refinement of ferrimagnetic barium ferrite, BaFe 12 O 19 . In: Journal of Crystallography. 125, 1967, p. 437, doi : 10.1524 / zkri.1967.125.125.437 .
- ↑ Data sheet Barium dodecairon nonadecaoxide from AlfaAesar, accessed on February 16, 2019 ( PDF )(JavaScript required) .
- ↑ Karl Schüler, Kurt Brinkmann: Permanent magnets materials and applications . Springer-Verlag, 2013, ISBN 978-3-642-93002-7 , pp. 203 ( limited preview in Google Book search).
- ↑ Susilawatia, Aris Doyanb, Khalilurrahman: Synthesis and characterization of barium hexaferrite with manganese (Mn) doping material as anti-radar , AIP Conference Proceedings 1801, 040007 (2017); doi : 10.1063 / 1.4973096 .