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

被引:59
作者
Roy, R [1 ]
Peelamedu, R [1 ]
Grimes, C [1 ]
Cheng, JP [1 ]
Agrawal, D [1 ]
机构
[1] Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA
关键词
D O I
10.1557/JMR.2002.0437
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
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, CoFe2,O-4, 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.
引用
收藏
页码:3008 / 3011
页数:4
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