Magnetic Properties of Amorphous Gd70(Fe, Ni)30 and Dy70(Fe, Ni)30 Alloys
The unique physical and mechanical properties of amorphous materials make them attractive for magnetic refrigeration applications. In an effort to develop advanced magnetic refrigerants, the magnetic properties of amorphous Gd70(Fe, Ni)30 and Dy70(Fe, Ni)30 alloys were investigated. The combination of 70 at.% Gd or Dy with different ratios of Fe and Ni produced amorphous materials with ordering temperatures covering the range of 300 K to 35 K. The coercive forces of both Gd-based and Dy-based alloys were negligible near their ordering temperatures. The magnetization properties of the alloys as a function of temperature in applied fields up to 5.6×106 A/m are presented. Magnetic entropy changes obtained from the field-dependent magnetization data are discussed. The broad nature of magnetic transitions in the amorphous alloys and its impact on the suitability of these materials as magnetic refrigerants are also discussed.
KeywordsAmorphous Alloy Amorphous Material Magnetic Transition Magnetic Entropy Change Magnetic Refrigerant
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