Novel Properties of Boron Added Amorphous Rare Earth-transition Metal Alloys for Giant Magnetostrictive and Magneto-optical Recording Materials

  • Published : 1998.09.01


Large magneto crystalline anisotropy energy and demagnetization energy of rare earth-transition metal (RF-TM) alloys play roles of bottlenecks towards their commercial applications for giant magnetostrictive and blue wavelength magneto optical recording materials, respectively. To solve the above problems, boron is added into amorphous RE-TM alloys to produce its electron transferring. The boron added amorphous RE-TM alloys show novel magnetic and magneto-optical properties as follows; 1) an amorphous $(Sm_{33}Fe_{76})$97B3 alloy obtains the magnetostriction of$ -550{times}10^{-6}$ at 400 Oe compared with saturation magnetostriction of$ -60{\times}10^{-6}$ in conventional Ni based alloys, 2) an amorphous$ (Nd_{33}Fe_{67})_{95}B_5$ alloy increases effective magnetic anisotropy to$ -0.5{\times}10^{-6} ergs/cm^3 from -3.5{\times}10^6 ergs/cm^3$ without boron, which correspond to the polar Kerr rotation angles of 0.52$^{\circ}$and 0.33$^{\circ}$, respectively. These results attribute to selective 2p-3d electron orbits exchange coupling (SEC).



  1. Ferromagnetism R. M. Bozorth
  2. J. Appl. Phys. v.57 R. J. Gambino;T. R. McGuire
  3. J. Mag. Magn. Mat. v.54-57 G. A. N. Conell
  4. J. Phys. F;Metal Phys. v.11 J. K. Lang;Y. Bare;P. A. Cox
  5. Ferromagnetic materials v.1 A. E. Clark
  6. INtroduction to magnetic materials B. D. Cullity
  7. Phys. Rev. v.B34 V. L. Moruzzi;P. M. Parcus;K. Schwarz;P. Mohn
  8. Phys. Rev. v.B23 R. P. Messmer
  9. N. Non-cryst. Sol. v.61;62 T. Fujiwara
  10. Solid State Commu. v.33 M. Matsuura;T. Nomoto;F. Itoh;K. Suzuki
  11. J. Appl. Phys. v.61 W. Reim;R. J. Gambino;R. R. Ruf;T. S. Plaskett
  12. J. Magn. Soc. Jpn. v.S1 no.SUP. 17 N. A. Bojarczuk;R. J. Gambino;T. S. Plaskett;P. Fumagalli;R. R. R. Ruf
  13. J. Phys. Metal. Phys. v.12 T. Fujiwara
  14. IEEE Trans. Magn. v.24 R. J. Gambino;T. S. Plaskett;R. R. Ruf