E.T. Dilmieva - Post-graduate Student, Bauman MSTU; Junior Research Scientist, Kotelnikov IRE RAS (Moscow) E-mail: kelvit@mail.ru; V.V. Koledov - Dr.Sc. (Phys.-Math.), Leading Research Scientist, Kotelnikov IRE RAS (Moscow); Y.S. Koshkidko - Ph.D. (Phys.-Math.), Research Scientist, International Laboratory of Strong Magnetic Fields and Low Temperatures (Wroclaw, Poland)

This work reports the results of the experimental studies of magnetocaloric effect (MCE) in Ni2.16Mn0.84Ga Heusler alloy with separate magnetic and structural phase transitions in adiabatic (∆T) and quasi isothermal (∆Q) regimes by direct methods in magnetic fields up to 10 T. The data obtained allow for comparing ∆T and ∆Q values in the vicinity of martensitic transition and Curie point. It is found maximal values of ∆T = 4,7 K at T = 311 K and ∆Q = 4,6 kJ/kg at T = 313 K in the fields H = 10 T. Optical observations of martensitic twins structure origin and evolution under the influence of high magnetic field confirm the reversible magnetic-field-induced martensitic transition at constant temperature T = 313 K in the field 14 T.

 

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