Magnetocaloric effect in ribbon samples of Heusler alloys Ni-Mn-M (M = In,Sn)

摘要

Direct measurements of the magnetocaloric effect in samples of rapidly quenched ribbons of Mn_(50)Ni_(40)In_(10) and Ni_(50)Mn_(37)Sn_(13) Heusler alloys with potential applications in magnetic refrigeration technology are carried out. The measurements were made by a precise method based on the measurement of the oscillation amplitude of the temperature in the sample while is subjected to a modulated magnetic field. In the studied compositions both direct and inverse magnetocaloric effects associated with magnetic (paramagnet-ferromagnet-antiferromagnet) and structural (austenite-martensite) phase transitions are found. Additional inverse magnetocaloric effects of small value are observed around the ferromagnetic transitions.