Table-like magnetocaloric effect and large refrigerant capacity of composite magnetic refrigerants based on LaFe_11.6Si_1.4H_y alloys

Lingtong Zhou，Yongbai Tang，Yungui Chen，Huaqiang Guo，Wenkai Pang，Xi Zhao

College of Materials Science and Engineering,Sichuan University

摘 要：Composite magnetic refrigerants were prepared by physical mixing LaFe_11.6Si_1.4H_y alloys with different Curie temperatures（Tc）. The phase structures of these LaFe_11.6Si_1.4H_y alloys were analyzed by X-ray diffraction（XRD） and the magnetocaloric effect（MCE） and refrigerant capacity（RC） of these composite magnetic refrigerants were investigated by experiment and calculation in this paper. The magnetocaloric effect（MCE） and refrigerant capacity（RC） of these composite magnetic refrigerants were investigated by experiment and calculation in this paper. The results indicate the experimental magnetic entropy change（-△S_M）-Tcurve corresponds reasonably with the（-△S_M）-Tcurve calculated by the linear combination of（-△S_M）-T curves of the single material. An optimal mixing ratio can make the composite magnetic refrigerant possess a table-like（-△S_M）-Tcurve which is beneficial to magnetic Ericsson cycle. When three LaFe_11.6Si_1.4H_y alloys with different T_c are mixed, the full width at half maximum(△T_FWHM) of（-△S_M）-T curves is about 48.7 K and the RC is about 177.76 J/kg under a magnetic field change of 2 T. The composite magnetic refrigerants based on LaFe_11.6Si_1.4H_y alloys can be promising candidates for near room temperature magnetic refrigeration and the work will be helpful to develop novel composite magnetic refrigerants with table-like MCE and large RC.

关键词：