Thermomagnetic and magnetocaloric properties of metamagnetic Ni-Mn-In-Co Heusler alloy in magnetic fields up to 140 kOe

¹ Kotelnikov Institute of Radio-engineering and Electronics of RAS, 125009 Moscow, Russia
² International Laboratory of High Magnetic Fields and Low Temperatures, 53-421 Wroclaw, Poland
³ Baikov Institute of Metallurgy and Material Science of RAS, 119991 Moscow, Russia
⁴ National University of Science and Technology “MISIS”, 119049 Moscow, Russia
⁵ Department of Physics, University of Oviedo, 33007 Oviedo, Spain
⁶ Western Michigan University, MI-49008 Kalamazoo, USA

^a e-mail: kama@cplire.ru

Published online: 3 July 2014

Abstract

High cooling power of magnetocaloric refrigeration can be achieved only at large amounts of heat, which can be transferred in one cycle from cold end hot end at quasi-isothermal conditions. The simple and robust experimental method of direct measuring of the transferred heat of materials with magnetocaloric effect (MCE) in thermal contact with massive copper block with definite heat capacity in quasi-isothermal regime was proposed. The vacuum calorimeter for the specific transferred heat ΔQ and adiabatic temperature change ΔT measurements of MCE materials in the fields of Bitter coil magnet up to H = 140 kOe was designed and tested on samples of Ni₄₃Mn_37.9In_12.1Co₇ Heusler alloy with inverse MCE in the vicinity of meta-magnetostructural phase transition (PT). It was found, that the magnetic field H = 80 kOe produces complete PT from martensite to austenite with ΔQ = - 1600 J/kg at initial temperature 273 K.