(GdxDy1-x) 12Co7 Magneto-thermal Eff ect

Yunyue Du

Abstract


Because of its own advantages such as energy saving and environmental protection, the greenhouse magnetic refrigeration technology is attracting more and more attention. Magnetic refrigeration materials as one of the key technology, its development has a very important role. This paper begins with a brief overview of the basic principles of magnetic refrigeration and the development of magnetic refrigeration materials. In this paper, the phase structure and Magnetocaloric eff ect of (GdxDy1-x) 12Co7 (x = 0.3, 0.5, 0.7, 0.8) series alloys were investigated by X-ray diff raction and magnetic properties measurements. The results show that all samples are monoclinic crystals, with the Gd composition increases, the Curie temperature of the alloy from 92K to 142K linear increase. In the case of an external magnetic fi eld of 2Td, the maximum magnetic entropy of the (GdxDy1-x) 12Co7 (x = 0.3, 0.5, 0.7, 0.8) series alloy becomes 6.93 J / kg · K. By analyzing the XRD patterns of the alloys and the graphs of the M-H and Arrott graphs, it is shown that the alloy is transformed from a secondary phase transition to a primary phase transition.

Keywords


(GdxDy1-x) 12Co7 system; Magnetic entropy change; Magnetocaloric eff ect

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