Table-like magnetocaloric effect and large refrigerant capacity in Gd65Mn25Si10-Gd composite materials for near room temperature refrigeration

Abstract Amorphous Gd 65 Mn 25 Si 10 as well as crystalline Gd have technologically significant Curie temperature and large magnetic entropy change. Two types of composite materials Gd 65 Mn 25 Si 10 -Gd were fabricated: laminating Gd sheets and amorphous Gd 65 Mn 25 Si 10 ribbons (multilayer composite) and hot pressing a mixture of amorphous Gd 65 Mn 25 Si 10 thin ribbons, Gd particles and a small amount of Sn powders (bulk composite). A table-like magnetocaloric effect (MCE) in a wide, commercially useful, temperature span of 73 K (220 K-293 K) were observed in these composites. The values of full-width at half maximum of (−Δ S M ) −  T plots (Δ T FWHM ) and enhanced refrigerant capacity (RC) for the multilayer and bulk composites are 212 K, 724 J/kg, and 248 K, 617 J/kg, respectively, for a field of 5 T. Large Δ T FWHM and RC values and the table-like (−Δ S M ) max feature suggest that both multilayer and bulk Gd 65 Mn 25 Si 10 -Gd composites can meet the requirements of different magnetic refrigeration based on Ericsson-cycle.