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Major phase transformations and magnetic property changes caused by electromagnetic fields at microwave frequencies

  • Rustum Roy (a1), Ramesh Peelamedu (a1), Craig Grimes (a1), Jiping Cheng (a1) and Dinesh Agrawal (a1)...

Abstract

We demonstrate in this paper that common crystalline phases can be made noncrystalline and hard magnets can be converted to soft magnets in the solid state in several seconds at temperatures far below the melting points. New crystal structures and magnetic structures of ferromagnetic oxides (ferrites such as BaFe12O19, CoFe2O4, Fe3O4, and ZnFe2O4, etc.) are formed by reacting either the stoichiometric mixture of oxides or the preformed phase-pure crystalline material in a pure H field (or E field) at microwave (2.45 GHz) frequencies. These major changes in the magnetic properties as well as major structural phase changes are caused by the magnetic field.

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Corresponding author

a)Address all correspondence to this author.102A Materials Research Laboratory, The Pennsylvania State University, University Park, Pennsylvania 16802.rroy@psu.edu

References

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Major phase transformations and magnetic property changes caused by electromagnetic fields at microwave frequencies

  • Rustum Roy (a1), Ramesh Peelamedu (a1), Craig Grimes (a1), Jiping Cheng (a1) and Dinesh Agrawal (a1)...

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