非晶态Fe-Zr-B-Dy合金的制备与磁热性能

非晶态磁热合金材料可以在很宽的温度范围内实现较大的磁制冷容量,其中铁基非晶态磁热合金因其具有近室温的磁熵变区间和低廉的成本受到广泛关注.本文通过感应熔炼铜辊甩带的方法成功制备出了一系列Fe_89?xZr₇B₄Dy_x(x=1,2,3,4)非晶态合金,并对其非晶形成能力和磁热性能进行了系统测试和分析.随着Dy含量的增加,该合金的玻璃形成能力得到改善,居里温度从296 K增加到334 K.磁熵变峰值和制冷能力也随着Dy含量的增加单调增长,在3 T的外加磁场下,Fe85Zr7B4Dy4合金的最大磁熵变达到了2.45 J K^?1 kg^?1,制冷能力为235 J kg^?1,相对于三元Fe-Zr-B体系,同一磁场下的磁熵变峰值提高60%以上.该非晶态合金原材料成本低廉,其磁热性能随着成分变化可以调控,居里温度远低于玻璃转变温度,能够保证材料在使用过程中的结构稳定性,有成为近室温的磁制冷工质的潜力.

Preparation and magnetocaloric properties of amorphous Fe-Zr-B-Dy alloys

Amorphous magnetocaloric alloys can achieve large magnetic refrigeration capacity in a wide temperature range.Ironbased 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 Fe_89?xZr₇B₄Dy_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.