Abstract
Fine particles of strontium hexaferrite, SrFe12O19, with a narrow size distribution have been synthesized hydrothermally from mixed aqueous solutions of iron and strontium nitrates under different synthesis conditions. The relationship between the synthesis variables (temperature, time and alkali molar ratio) and the magnetic properties has been investigated. The results have shown that, as the synthesis temperature increases, the saturation magnetization of the particles increases up to a plateau and the coercivity decreases. As the alkali molar ratio R(=OH−/NO −3 ) increases, the coercivity decreases and goes through a local minimum, while the saturation magnetization increases and goes through a local maximum. Increasing the synthesis time from 2 h to 5 h has no significant effect on the saturation magnetization, but decreases the coercivity. An anisotropic sintered magnet with a high saturation magnetization value of 67.26 e.m.u g−1 (4320 G)‡ has been fabricated from the hydrothermally synthesized powders.
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References
H. Kojima, in “Ferromagnetic Materials: A Handbook on the Properties of Magnetically Ordered Substances”, Vol. 3, edited by E. P. Wohlfarth (North-Holland, Amsterdam, 1982) Ch. 5, pp. 305–91.
H. Stäblein, ibid. Vol. 3, Ch. 7, pp. 441–602.
Sutarno, W. S. Bowman and G. E. Alexander, J. Canad. Ceram. Soc. 39 (1970) 33.
S. K. Date, C. E. Deshpande, S. D. Kulkarni and J. J. Shrotri, in “Proceedings of the 5th International Conference on Ferrites”, Bombay, India, 10–13 Jan., 1989, edited by C. M. Srivastava and M. J. Patni (1990) pp. 55–60.
V. V. Pankov, M. Pernet, P. Germi and P. Mollard, J. Magn. Magn. Mater. 120 (1993) 69.
K. Haneda, C. Miyakawa and K. Goto, IEEE Trans. Magn. MAG 23 (1987) 3134.
D. bahadur and D. chakravorty, in “Proceedings of the International Conference on Ferrites”, India (1989) pp. 189–93.
H. Sato and T. Umeda, J. Mater. Trans. 34 (1) (1993) 76.
R. J. Routil and D. Barham, J. Canad. Chem. 52 (1974) 3235.
C. H. Lin, Z. W. Shih, T. S. Chin, M. L. Wang and Y. C. Yu, IEEE Trans. Magn. MAG 26 (1990) 15.
A. Ataie, I. R. Harris and C. B. Ponton, in British Ceramic Proceedings 52, Electroceramics: Production, Properties and Microstructures”, Proceedings of a Symposium held as part of the Condensed Matter and Materials Physics Conference, University of Leeds, 20–22 December 1993, edited by W. E. Lee and A. Bell (Institute of Materials, London, (1994) pp. 273–81.
A. Ataie, M. R. Piramoon, C. B. Ponton and I. R. Harris, J. Mater. Sci. December, 1994.
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Relationship between the c.g.s and S.I.units which are used in this paper are as follows: 1 erg = 10−7 J, 1 e.m.u. cm−3 = 12.57×10−7 Wom−2 (tesla), 1 oersted (Oe) = 79.6 A m−1, 1 G = 10−4 tesla (T).
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Ataie, A., Harris, I.R. & Ponton, C.B. Magnetic properties of hydrothermally synthesized strontium hexaferrite as a function of synthesis conditions. Journal of Materials Science 30, 1429–1433 (1995). https://doi.org/10.1007/BF00375243
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DOI: https://doi.org/10.1007/BF00375243