A series of the amorphous Gd75-55A125-5Fe0-40 alloy ribbons were prepared by melt spinning. The structure, magnetic properties and magnetocaloric effect (MCE) of these alloys were investigated. The prepared samples ...A series of the amorphous Gd75-55A125-5Fe0-40 alloy ribbons were prepared by melt spinning. The structure, magnetic properties and magnetocaloric effect (MCE) of these alloys were investigated. The prepared samples have shown the characteristics of a second-order phase transition with zero hysteresis loss and the Tc can be tuned by changing the Fe contents. For the different compositions, the magnetic entropy change (-△Sm) for a field change of 0-5 T reached a maximum value of 7.14 J kg 1 K1 in the Gd70A120Fel0 alloy near its Curie temperature (To) of 149 K. The non-linear composition dependence of (- △ Sin) could be caused by the competitions between Fe-Fe, Fe-Gd and Gd-Gd interactions. The refrigeration capacity (RC) values of these al- loys are about 532-780 J/kg under a magnetic field change of 0-5 T. The results indicate that amorphous GdFeA1 alloys can be considered as ideal candidates for a magnetic refrigerant in the temperature range of 104-222 K.展开更多
基金supported by the Guangdong Provincial Science and Technology Program (Grant Nos. 2010B050300008, 2007B010600043)the Fundamental Research Funds for the Central Universities, South China University of Technology (Grant No. 2009ZM0291)
文摘A series of the amorphous Gd75-55A125-5Fe0-40 alloy ribbons were prepared by melt spinning. The structure, magnetic properties and magnetocaloric effect (MCE) of these alloys were investigated. The prepared samples have shown the characteristics of a second-order phase transition with zero hysteresis loss and the Tc can be tuned by changing the Fe contents. For the different compositions, the magnetic entropy change (-△Sm) for a field change of 0-5 T reached a maximum value of 7.14 J kg 1 K1 in the Gd70A120Fel0 alloy near its Curie temperature (To) of 149 K. The non-linear composition dependence of (- △ Sin) could be caused by the competitions between Fe-Fe, Fe-Gd and Gd-Gd interactions. The refrigeration capacity (RC) values of these al- loys are about 532-780 J/kg under a magnetic field change of 0-5 T. The results indicate that amorphous GdFeA1 alloys can be considered as ideal candidates for a magnetic refrigerant in the temperature range of 104-222 K.