Punto di Curie

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Dicesi punto di Curie, o temperatura di Curie, quel valore di temperatura al di sopra del quale un materiale ferromagnetico perde alcune delle sue proprietà (quale la corrispondenza non univoca tra campo esterno e magnetizzazione), e si comporta similmente ad un paramagnetico. Il disordine termico sopra questa temperatura è sufficiente a vincere il contributo energetico dell'interazione di scambio interatomica e la struttura ordinata dei domini magnetici viene quindi distrutta. La suscettività magnetica segue la legge di Curie-Weiss:

\chi_m = \frac {C \ \rho}{T - T_c}

dove C è una costante caratteristica del materiale, \rho è la densità e T_c la temperatura di Curie in kelvin.

Esempi di temperature di Curie:

Materiale Temperatura (K) (°C)
Ferro (Fe) 1043 K 768 °C
Cobalto (Co) 1390 K 1115 °C
Nichel (Ni) 620 K 345 °C
Mumetal 570 K 295 °C

Bibliografia[modifica | modifica sorgente]

  • K. H. J. Buschow, Encyclopedia of materials : science and technology, Elsevier, 2001. ISBN 0-08-043152-6.
  • Charles Kittel, Introduction to Solid State Physics, sixth, John Wiley & Sons, 1986. ISBN 0-471-87474-4.
  • Ramon Pallàs-Areny e John G Webster, Sensors and Signal Conditioning, 2nd, John Wiley & Sons, 2001, pp. 262–263. ISBN 978-0-471-33232-9.
  • Nicola A. Spaldin, Magnetic materials : fundamentals and applications, 2nd, Cambridge, Cambridge University Press, 2010. ISBN 978-0-521-88669-7.
  • Harald Ibach e Hans Lüth, Solid-state physics : an introduction to principles of materials science, 4th extensively updated and enlarged, Berlin, Springer, 2009. ISBN 978-3-540-93803-3.
  • Robert A Levy, Principles of Solid State Physics, Academic Press, 1968. ISBN 978-0124457508.
  • H.Y Fan, Elements of Solid State Physics, Wiley-Interscience, 1987. ISBN 978-0-471-85987-1.
  • Adrianus J Dekker, Solid State Physics, Macmillan, 1958. ISBN 978-0-333-10623-5.
  • N Cusack, The Electrical and Magnetic Properties of Solids, Longmans, Green, 1958.
  • J.R. Hook, H.E. Hall, Solid state physics, 2nd, Chichester, Wiley, 1994. ISBN 0-471-92805-4.
  • André Guinier ; Rémi Jullien, The solid state from superconductors to superalloys, Pbk., Oxford, Oxford Univ. Press, 1989. ISBN 0-19-855554-7.
  • K. Mendelssohn, The quest for absolute zero : the meaning of low temperature physics, with S.I. units., 2nd, London, Taylor and Francis, 1977. ISBN 0-85066-119-6.
  • H.P. Myers, Introductory solid state physics., 2nd ed., London, Taylor & Francis, 1997. ISBN 0-7484-0660-3.
  • Charles Kittel, Introduction to solid state physics, 7. ed., New York [u.a.], Wiley, 1996. ISBN 0-471-11181-3.
  • John Palmer, Planar Ising correlations, [Online-Ausg.]., Boston, Birkhäuser, 2007. ISBN 978-0-8176-4620-2.
  • Dalía S Bertoldi, Bringa, Eduardo M; Miranda, E N, Analytical solution of the mean field Ising model for finite systems in Journal of Physics: Condensed Matter, vol. 24, n. 22, 6 June 2012, pp. 226004. Bibcode:2012JPCM...24v6004B, DOI:10.1088/0953-8984/24/22/226004. URL consultato il 12/02/2013.
  • Robert Brout, Phase Transitions, New York, Amsterdam, W.A.Benjamin.INC, 1965.
  • C. Rau, Jin, C.; Robert, M., Ferromagnetic order at Tb surfaces above the bulk Curie temperature in Journal of Applied Physics, vol. 63, n. 8, 1 January 1988, pp. 3667. Bibcode:1988JAP....63.3667R, DOI:10.1063/1.340679.
  • R. Skomski, Sellmyer, D. J., Curie temperature of multiphase nanostructures in Journal of Applied Physics, vol. 87, n. 9, 1 January 2000, pp. 4756. Bibcode:2000JAP....87.4756S, DOI:10.1063/1.373149.
  • Victor Lopez-Dominguez, Hernàndez, Joan Manel; Tejada, Javier; Ziolo, Ronald F., Colossal Reduction in Curie Temperature Due to Finite-Size Effects in CoFe O Nanoparticles in Chemistry of Materials, vol. 25, n. 1, 8 January 2013, pp. 6–11. DOI:10.1021/cm301927z.
  • S. K. Bose, Kudrnovský, J.; Drchal, V.; Turek, I., Pressure dependence of Curie temperature and resistivity in complex Heusler alloys in Physical Review B, vol. 84, n. 17, 1 November 2011. arXiv:1010.3025, Bibcode:2011PhRvB..84q4422B, DOI:10.1103/PhysRevB.84.174422.
  • John G. Webster, The measurement, instrumentation, and sensors handbook, [Online-Ausg.], Boca Raton, Fla., CRC Press published in cooperation with IEEE Press, 1999. ISBN 0-8493-8347-1.
  • Attay Kovetz, The principles of electromagnetic theory., 1st published., Cambridge [England], Cambridge University Press, 1990. ISBN 0-521-39997-1.
  • Rolf E. Hummel, Electronic properties of materials, 3. ed., New York [u.a.], Springer, 2001. ISBN 0-387-95144-X.
  • K.J. Pascoe, Properties of materials for electrical engineers., New York, N.Y., J. Wiley and Sons, 1973. ISBN 0-471-66911-3.
  • Paulsen, Jason A. Lo, Chester C H; Snyder, John E.; Ring, A. P.; Jones, L. L.; Jiles, David C. Jones, Study of the Curie temperature of cobalt ferrite based composites for stress sensor applications, 39 , Issue: 5, Sept. 2003, pp. 3316–3318.
  • Hae Jin Hwang, Nagai, Toru; Ohji, Tatsuki; Sando, Mutsuo; Toriyama, Motohiro; Niihara, Koichi, Curie Temperature Anomaly in Lead Zirconate Titanate/Silver Composites in Journal of the American Ceramic Society, vol. 81, n. 3, 21 January 2005, pp. 709–712. DOI:10.1111/j.1151-2916.1998.tb02394.x.
  • Aymeric Sadoc, Mercey, Bernard; Simon, Charles; Grebille, Dominique; Prellier, Wilfrid; Lepetit, Marie-Bernadette, Large Increase of the Curie Temperature by Orbital Ordering Control in Physical Review Letters, vol. 104, n. 4, 1 January 2010. arXiv:0910.3393, Bibcode:2010PhRvL.104d6804S, DOI:10.1103/PhysRevLett.104.046804.
  • Pierre Curie - Biography in Nobelprize.org, From Nobel Lectures, Physics 1901-1921, Elsevier Publishing Company, Amsterdam, 1967, The Nobel Foundation 1903. URL consultato il 14/03/2013.


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