Achievement of giant cryogenic refrigerant capacity in quinary rare-earths based high-entropy amorphous alloy

Magnetic refrigeration(MR)by utilizing the magnetocaloric(MC)effect is recognized as one of the most potential promising solid state environmentally friendly and high efficiency alternative method to the well-used state-of-the-art gas compression cooling technique.In this work,a systematic investigation of quinary equi-atomic rare-earths(RE)based Er_(20) Ho_(20) Gd_(20) Ni_(20) Co_(20) high-entropy(HE)amorphous alloy in terms of the microstructure,magnetic and magnetocaloric(MC)properties have been reported.The Er_(20) Ho_(20) Gd_(20) Ni_(20) Co_(20) exhibits promising glass forming ability with an undercooled liquid region of 72 K.Excellent cryogenic MC performances can be found in wide temperature from∼25 and∼75 K,close to H_(2) and N_(2) liquefaction,respectively.Apart from the largest magnetic entropy change(-S M)reaches 17.84 J/(kg K)with 0-7 T magnetic field change,corresponding refrigerant capacity(RC)attains a giant value of 1030 J/kg.The promising cryogenic MC performances together with the unique HE amorphous characterizations make the quinary Er_(20) Ho_(20) Gd_(20) Ni_(20) Co_(20) HE amorphous alloy attractive for cryogenic MR applications.