Relative Cooling Power Enhancement by Tuning Magneto-structural Stability in Ni-Mn-In Heusler Alloys

Abstract

Off-stoichiometric Ni${}_2$MnIn Heusler alloys have drawn recent attention due to their large magnetocaloric entropy change associated with the first-order magneto-structural transition. Here we present crystal structural, calorimetric and magnetic studies of three compositions. Temperature-dependent X-ray diffraction shows clear structural transition from a 6M modulated monoclinic to a L2${}_1$ cubic. A significant enhancement of relative cooling power (RCP) was achieved by tuning the magnetic and structural stability through minor compositional changes, with the measured results quantitatively close to the prediction as a function of the ratio between the martensitic transition ($T_m$) temperature and austenite Curie temperature ($T_C$) although the maximal magnetic induced entropy change ($\Delta S_{max}$) reduction is observed in the same time. The results provided an evaluation guideline of RCPs as well as magnetic-induced entropy change in designing practical active materials.

References in corpus (3)

• Direct Measure of Giant Magnetocaloric Entropy Contributions in Ni-Mn-In
• Calorimetric and magnetic study for Ni${}_{50}$Mn${}_{36}$In${}_{14}$ and relative cooling power in paramagnetic inverse magnetocaloric systems
• Lattice vibrations boost demagnetization entropy in shape memory alloy

Cited by in corpus (2)

• Structural, magnetic, and magnetocaloric properties of Fe2CoAl Heusler nanoalloy
• Magnetocaloric properties and critical behavior of Co${}_2$Cr${}_{1-x}$Mn${}_x$Al Heusler alloys