Table-like magnetocaloric effect and large refrigerant capacity of composite magnetic refrigerants based on LaFe11.6Si1.4Hy alloys

Abstract

Composite magnetic refrigerants were prepared by physical mixing LaFe11.6Si1.4Hy alloys with different Curie temperatures (TC). The phase structures of these LaFe11.6Si1.4Hy 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 (−ΔSM)–T curve corresponds reasonably with the (−ΔSM)–T curve calculated by the linear combination of (−ΔSM)–T curves of the single material. An optimal mixing ratio can make the composite magnetic refrigerant possess a table-like (−ΔSM)–T curve which is beneficial to magnetic Ericsson cycle. When three LaFe11.6Si1.4Hy alloys with different TC are mixed, the full width at half maximum (ΔTFWHM) of (−ΔSM)–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 LaFe11.6Si1.4Hy 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.