Preparation and magnetocaloric properties of amorphousFe-Zr-B-Dy alloys

Abstract

Amorphous magnetocaloric alloys can achieve large magnetic refrigeration capacity in a wide temperature range. Iron-based amorphous magnetocaloric alloys are widely concerned because of their near room-temperature magnetic entropy change range and low cost. In this paper, a series of Fe89− x Zr7B4Dy x ( x= 1, 2, 3, 4) amorphous alloys have been successfully prepared by the single roller melt-spinning method. The structures, thermodynamic parameters, and magnetocaloric properties have been systematically tested and analyzed for the alloys. With the increase of Dy content, the glass forming ability of the alloy was increased, and the Curie temperature got increased from 296 to 334 K. The maximum entropy change of Fe85Zr7B4Dy4 alloy is 2.45 J K−1 kg−1 and the refrigeration capacity is 235 J kg−1 at 3 T applied magnetic field. Compared with the ternary Fe-Zr-B system, the peak value of magnetic entropy change is increased by more than 60% under same magnetic field. The raw material of the amorphous alloy has low cost, and its Curie temperature can be adjusted with the change of composition. The Curie temperature is far lower than the glass transition temperature, which can ensure the structural stability of the material in the application process, and it is expected to become a magnetic refrigeration working medium near room temperature.