Magnetostructural transitions and magnetocaloric effects in Ni50Mn35In14.25B0.75 ribbons

Sudip Pandey,Abdiel Quetz,C F Sánchez-Valdés,Igor Dubenko,Naushad Ali,Shane Stadler,P J Ibarra-Gaytan,Anil Aryal,Jose Luis Sanchez Llamazares

doi:10.1063/1.5006467

Abstract

The structural, thermal, and magnetic behaviors, as well as the martensitic phase transformation and related magnetocaloric response of Ni50Mn35In14.25B0.75 annealed ribbons have been investigated using room-temperature X-ray diffraction (XRD), differential scanning calorimetry (DSC), and magnetization measurements. Ni50Mn35In14.25B0.75 annealed ribbons show a sharper change in magnetization at the martensitic transition, resulting in larger magnetic entropy changes in comparison to bulk Ni50Mn35In14.25B0.75. A drastic shift in the martensitic transformation temperature (TM) of 70 K to higher temperature was observed for the annealed ribbons relative to that of the bulk (TM = 240 K). The results obtained for magnetic, thermal, structural, and magnetocaloric properties of annealed ribbons have been compared to those of the corresponding bulk alloys.

Highlights

The off-stoichiometric Ni-Mn-In Heusler systems have been drawing interest due to their temperature-induced magnetostructural transitions (MST), which are responsible for extreme physical properties like giant normal and inverse magnetocaloric effects,[1,2,3] giant magnetoresistance,[4,5] large anomalous Hall effects,[6] and magnetic shape memory effects.[7]
The X-ray diffraction (XRD) pattern of the ribbons is similar to that of bulk Ni-Mn-In based Heusler alloys in the phase coexistence region exhibiting a magnetostructural transition near room temperature.[22]
We have investigated the magnetostructural transitions, magnetic, and magnetocaloric properties of Ni50Mn35In14.25B0.75 annealed ribbons

Summary

Introduction

The off-stoichiometric Ni-Mn-In Heusler systems have been drawing interest due to their temperature-induced magnetostructural transitions (MST), which are responsible for extreme physical properties like giant normal and inverse magnetocaloric effects,[1,2,3] giant magnetoresistance,[4,5] large anomalous Hall effects,[6] and magnetic shape memory effects.[7] Most of the research for the Ni-Mn-In based Heusler alloys have been being carried out for bulk materials by means of conventional melting techniques followed by lengthy high-temperature thermal annealing.[8,9,10] Currently, a variety of magnetocaloric materials have been successfully synthesized in the form of ribbons by rapid quenching using the melt-spinning technique.[11,12,13,14,15] It has been observed that single-phase homogeneous polycrystalline materials are formed in melt-spun ribbons, avoiding the need for longterm thermal annealing of their bulk counterparts.[13,16] In addition, previous studies indicate that if synthesis condition are properly controlled, ribbons produced by melt spinning techniques may have a highly textured microstructure and negligible demagnetization field along the ribbon length.[17,18] It has been reported that melt-spinning effectively promotes more homogeneous materials, and reduces the annealing time with improved MCE properties.[12,15,19]

Methods

Results

Conclusion