The polycrystalline MgCrxFe2-xO4 ferrites (0.0 ? x ? 1.0) were prepared by conventional solid state ceramic sintering technique in air at 1300?C. X-ray diffraction experiments were carried out on all the samples in order to characterize the materials at room temperature. The X-ray diffraction patterns showed sharp peaks indicating the formation of single phased cubic spinel structure. The lattice parameters of the samples were determined from the X-ray diffraction data using Nelson-Riley extrapolation method. It was found that the lattice parameter decreased with increasing Cr concen- tration obeying Vegard’s law. Magnetic properties of the samples were measured using an Impedance Analyzer. Real and imaginary parts of the complex permeability, loss factor and quality factor were measured as the function of frequency at three different sintering temperatures 1250?C, 1300?C and 1350?C for all the samples in the frequency range 1 kHz to 13 MHz. Frequency stability of the real part of permeability increases with increasing Cr concentration and also with sintering temperature. Imaginary part of permeability decreases with increasing frequency and increased with increasing both of the Cr content and sintering temperature. Loss factor decreased with increasing frequency while the quality factor (Q) increased with increasing frequency for all the samples. The temperature de- pendence of initial permeability was measured for all the samples sintered at 1300?C. The Curie temperature (Tc) was determined from the -T curves. The values of Tc were found to be 733 K, 657 K, 583 K, 468 K, 400 K and 317 K for x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0, respectively.
KeywordsFerritesSpinel StructureMagnetic PropertiesPermeabilityLoss FactorCurie Temperature
P. V. Reddy and T. S Rao, “Dielectric Behaviour of Mixed Li-Ni Ferrites at Low Frequencies,” Journal of Less Common Metals, Vol. 86, 1982, pp. 255-261. doi:10.1016/0022-5088(82)90211-9
M. A. Ahmed, “Electrical Properties of Co-Zn Ferrites,” Physica Status Solidi (A), Vol. 111, No. 2, 1989, pp. 567-572. doi:10.1002/pssa.2211110222
R. Lebourgeois, C. Le Fur, M. Labyre, M Pate and J.-P. Ganne, “Permeability Mechanisms in High Frequency Polycrystalline Ferrites,” Journal of Magnetism and Magnetic Materials, Vol. 160, 1996, pp. 329-332. doi:10.1016/0304-8853(96)00217-X
A. K. M. Zakaria, M. A. Asgar, S.-G. Eriksson, F. U. Ahmed, S. M. Yunus and H. Rundl?f, “The Study of Magnetic Ordering in the Spinel System ZnxNi1-xFeCrO4 by Neutron Diffraction,” Journal of Magnetism and Magnetic Materials, Vol. 265, No. 3, 2003, pp. 311-320. doi:10.1016/S0304-8853(03)00280-4
A. K. M. Zakaria, M. A. Asgar, S.-G. Eriksson, F. U. Ahmed, S. M. Yunus, R. Delaplane, V. Stanciu and P. Svedlindh, “Crystallographic and Magnetic Properties of the Spinel Type Solid Solution Zn0.4Co0.6AlxFe2-xO4 (0 ? x ?1),” Materials Research Bulletin, Vol. 39, No. 7-8, 2004, pp. 1141-1157. doi:10.1016/S0025-5408(04)00053-4
D. J. Shellmyer and S. Nafis, “Random Magnetism in Amorphous Rare-Earth Alloys,” Journal of Applied Physics, Vol. 57, No. 8, 1985, pp. 3584-3588. doi:10.1063/1.335014
E. M. Chudnovsky, “Magnetic Properties of Amorphous Ferromagnets,” Journal of Applied Physics, Vol. 64, No. 10, 1988, pp. 5770-5775. doi:10.1063/1.342227
G. A. Sawatsky, F. Van Der Woude and A. H. Morrish, “M?ssbauer Study of Several Ferrimagnetic Spinels,” Physical Review, Vol. 187, No. 2, 1969, pp. 747-757. doi:10.1103/PhysRev.187.747
G. A. Petti and P. W. Forester, “M?ssbauer Study of Co- balt-Zinc Ferrites,” Physical Review B, Vol. 4, No. 11, 1971, pp. 3912-3923. doi:10.1103/PhysRevB.4.3912
G. A. Sawatsky, F. Van Der Woude and A. H. Morrish, “Cation Distributions in Octahedral and Tetrahedral Sites of the Ferrimagnetic Spinel CoFe2O4,” Journal of Applied Physics, Vol. 39, No. 2, 1968, pp. 1204-1205. doi:10.1063/1.1656224
R. Plumier, “Reinvestigation of Magnetic Structures of CoCr2O4 and MnCr2O4 Obtained by Neutron Diffrac- tion,” Journal of Applied Physics, Vol. 39, No. 2, 1968, pp. 635-636. doi:10.1063/1.2163559
J. L. Snoek, “New Development in Ferrimagnetic Materi- als”, Elsevier, Amsterdam, 1947.
N?el Louis, “Prop?rti?s Magn?tique des Ferrites; Ferri- magnetism et Antiferromagnetism,” Annales de Physique, Vol. 3, 1948, pp. 137-198.
J. Smit, and H. P. J. Wijn, “Ferrites,” John Wiley & Sons Inc., New York, 1959.
K. J. Standley, “Oxide Magnetic Materials,” Oxford university Press, Oxford, 1972.
J. S. Smart, “The Néel Theory of Ferrimagnetism,” Ame- rican Journal of Physics, Vol. 23, No. 6, 1955, p. 356. doi:10.1119/1.1934006
E. W. Gorter, “Some Properties of Ferrites in Connection with Their Chemistry,” Proceedings of the IRE, Vol. 43, No. 12, 1955, pp. 1945-1973.
R. F. Soohoo, “Theory and Applications of Ferrites,” Prentice Hall, Engle-Wood Cliffs, 1960.
S. J. Shukla, K. M. Jadhav and G. K. Bichile, “Influence of Mg2+ Substitution on Magnetic Properties of Co-Fe- Cr-O Spinel Ferrite System,” Journal of Magnetism and Magnetic Materials, Vol. 195, No. 3, 1999, pp. 692-698.
L. Vegard, “Die Konstitution der Mischkristalle und Die Raumfüllung der Atome,” Journal of Applied Physics, Vol. 5, 1921, pp. 17-26.
C. Kittel, “Introduction to Solid State Physics,” John Wiley & Sons Inc., New York, 1976.
R. Valenzuela, “Magnetic Ceramics,” Cambridge Univer- sity Press, London, 1994.
E. Cedillo, J. Ocampo, V. Rivera and R. Valenzuela, “An Apparatus for the Measurement of Initial Magnetic Per- meability as a Function of Temperature,” Journal of Physics E: Scientific Instrument, Vol. 13, No. 4, 1980, pp. 383-386. doi:10.1088/0022-3735/13/4/005
R. Valenzuela, “A Sensitive Method for the Determina- tion of the Curie Temperature in Ferrimagnets,” Journal of Materials Science, Vol. 15, No. 12, 1980, pp. 3173- 3174. doi:10.1007/BF00550394
M. A. Gilleo, “Superexchange Interaction in Ferrimagnetic Garnets and Spinels which Contain Randomly Incomplete Linkages,” Journal of Physics and Chemistry of Solids, Vol. 13, No. 1-2, 1960, pp. 33-39. doi:10.1016/0022-3697(60)90124-4
B. D. Cullity, “Introduction to Magnetic Materials,” Ad- dision-Wisley Publishing Company Inc., California, 1972.
S. Chikazumi, “Physics of Magnetism,” John Wiely & Sons Inc., New York, 1966.
T. Nakamura, “Low-Temperature Sintering of Ni-Zn-Cu Ferrite and Its Permeability Spectra,” Journal of Magnetism and Magnetic Materials, Vol. 168, No. 3, 1994, pp. 285-291. doi:10.1016/S0304-8853(96)00709-3
A. Globus and M. Guyot, “Determination of Initial Mag- netization Curve from Crystallites Size and Effective Anisotropy Field,” IEEE Transactions on Magnetics, Vol. 7, No. 3, 1971, pp. 617-622. doi:10.1109/TMAG.1971.1067200
G. Baca, R. Vanezuela, M. A. Escober and L. M. Magna, “Temperature Dependence of the Critical Magnetic Field in Polycrystalline Ferrites,” Journal of Applied Physics, Vol. 57, No. 8, 1983, pp. 4183-4185. doi:10.1063/1.334605
R. F. Pearson and A. D. Annis, “Anisotropy of Fe3+ Ions in Yttrium Iron Garnet,” Journal of Applied Physics, Vol. 39, No. 2, 1968, pp. 1338-1339. doi:10.1063/1.1656290
J. Kanamori, G. Rado, and H. Suhl, “Magnetism,” Aca- demic, London, 1964.
A. Globus, “Magnetization Mechanisms: Some Physical Considerations about the Domain Wall Size Theory of Magnetization Mechanisms,” Journal de Physique Col- lques, Vol. 38, 1977, pp. C1-C15.
G. P. Kramar and Y. I. Panova, “Resonance and Rela- xation of Domain Walls in Polycrystaline Ferrites,” Physica Status Solidi (A), Vol, 77, No. 2, 1983, pp. 483-489. doi:10.1002/pssa.2210770210
J. Smit, “Magnetic Properties of Material,” McGraw-Hill, New York, 1977.
K. J. Overshott, “The Causes of the Anomalous Loss in Amorphous Ribbon Materials,” IEEE Transactions on Magnetics, Vol. 17, No. 6, 1981, pp. 2698-2700. doi:10.1109/TMAG.1981.1061648
F. G. Brockman, P. H. Dowling and W. G. Steneck, “Di- mensional Effects Resulting from a High Dielectric Con- stant Found in a Ferromagnetic Ferrite,” Physical Review, Vol. 77, No. 1, 1950, pp. 85-93. doi:10.1103/PhysRev.77.85