Results 181 to 190 of about 2,555 (212)

Co, Ti, Mn-precipitated barium hexaferrite powders

IEEE Transactions on Magnetics, 1994
Barium ferrites substituted by Co, Ti, and Mn, produced by the citrate method have been studied. The substitution x in BaCo/sub x/Ti/sub x/Mn/sub y/Fe/sub 12-2x-y/O/sub 19/ has been varied from 0.2-2.O i./f.u. and the substitution of Mn y=0.1 i./f.u. Magnetic parameters were measured by the vibration magnetometer.
M. Michalikova, A. Gruskova, R. Vicen, J. Lipka, J. Slama   +4 more
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Topochemical Sintering and Characterization of Barium Hexaferrite

Transactions of the Indian Ceramic Society, 1997
The topochemical sintering of barium hexaferrite utilizing stoichiometric mixtures of BaCO3 and αFe2O3/α-FeOOH raw materials has been investigated. The densification behaviour of BaO.6Fe2O3 in the temperature range of 1273 to 1573 K is studied with the help of a dilatometer. The nonisothermal dcnsification kinetics is derived from dilatometrie results.
J. L. Gumaste, M. M. Godkhindi, P. G. Mukunda, H. S. Ray   +3 more
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Metal-barium hexaferrite composites as permanent magnets

Ceramics International, 1977
Abstract Barium ferrite powders have been coated with a thin layer of a cobalt phosphorus or nickel phosphorus alloy by chemical reduction from aqueous solutions with hypophosphite, after the usual sensitization-activation pretreatments. The operation parameters of the deposition baths have been varied to modify the phosphorus content, the morphology
G. Asti, P. Cavallotti, R. Roberti
openaire   +1 more source

Current tunable barium hexaferrite millimeter wave resonator

Microwave and Optical Technology Letters, 2018
AbstractThis report is on non‐linear magneto‐electric (ME) interactions due to an electric current in single crystal M‐type barium hexaferrite (BaM). The interaction results in variations in the magnetic order parameters and manifests as tuning of magnetic modes in a BaM resonator in the U‐band.
M. A. Popov, I. V. Zavislyak, G. Srinivasan   +2 more
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Synthesis and characterization of barium hexaferrite nanoparticles

Journal of Materials Processing Technology, 2007
Abstract This investigation dealt with the synthesis of nanocrystalline barium hexaferrite (BaFe12O19) powders through the co-precipitation–calcination route. The ferrite precursors were obtained from aqueous mixtures of barium and ferric chlorides by co-precipitation of barium and iron ions using 5 M sodium hydroxide solution at pH 10 in room ...
M. Radwan, M.M. Rashad, M.M. Hessien
openaire   +1 more source

Barium hexaferrite magnet by topotactic reaction method

Journal of Materials Science, 1988
A new topotactic sintering method using αFe2O3 (obtained from αFeO · OH) and BaCO3 is developed for preparing cheaper grain oriented barium hexaferrite. αFe2O3 and BaCO3 (precipitate grade) are wet mixed in a ball mill in stoichiometric proportion. The mixed slurry is then dried at 110° C for about 12h. The dried powder mixture containing moisture as a
J. L. Gumaste, B. B. Nayak, R. K. Galgali, B. C. Mohanty   +3 more
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Catalytic combustion of methane over barium hexaferrites

Catalysis Letters, 1997
Barium hexaferrite BaFe12O19 and iridium-containing barium hexaferrites have been prepared by the citrates gel method. Their catalytic activity in methane combustion has been evaluated. BaFe12O19 is an efficient catalyst for this reaction, and the introduction of iridium in the hexaferrite structure does not improve this activity.
Favre, A., Guillaume, N., Millet, J.M.M., Primet, M.   +3 more
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Barium hexaferrite ferrofluids – preparation and physical properties

Journal of Magnetism and Magnetic Materials, 1999
Abstract Barium hexaferrite BaFe 12−2 x Ti x Co x O 19 ferrofluids have been prepared for the first time using oleic acid as surfactant and Isopar M ® as carrier liquid. The initial susceptibility versus temperature for zero-field cooling of the ferrofluid was obtained by a vibrating sample magnetometer. TEM pictures of the fluid show isolated
R Müller, R Hiergeist, H Steinmetz, N Ayoub, M Fujisaki, W Schüppel   +5 more
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The low-temperature formation of barium hexaferrites

Journal of the European Ceramic Society, 2006
Abstract We have investigated the formation of barium hexaferrites with the compositions BaFe 12 O 19 and Ba 2 Co 2 Fe 12 O 22 using precipitation in ethanol. A mechanism for the formation was proposed, based on the results of thermal analysis, X-ray powder diffraction, electron microscopy and the magnetic properties of powders prepared under ...
Darja Lisjak, Miha Drofenik
openaire   +1 more source

Coefficients of thermal expansion for barium hexaferrite

Journal of Applied Physics, 1996
The thermal expansion coefficients along the a axis (αa) and c axis (αc) of barium hexaferrite were measured from room temperature to 850 °C. The thermal expansion of barium hexaferrite along the a axis and c axis was found to be linear as a function of temperature, indicating constant thermal expansion coefficients over this temperature range.
P. C. Dorsey, S. B. Qadri, J. L. Feldman, J. S. Horwitz, P. Lubitz, D. B. Chrisey, J. B. Ings   +6 more
openaire   +1 more source