Magnetic and magnetocaloric properties of Ni-Mn-Cr-Sn Heusler alloys under the effects of hydrostatic pressure

Sudip Pandey,Naushad Ali,Anil Aryal,Abdiel Quetz,Shane Stadler,Ahmad Us Saleheen,Igor Dubenko,Jing-Han Chen

doi:10.1063/1.5005802

Abstract

The magnetic, thermal, and magnetocaloric properties of Ni45Mn43CrSn11 Heusler alloy have been investigated using differential scanning calorimetry and magnetization with hydrostatic pressure measurements. A shift in the martensitic transition temperature (TM) to higher temperatures was observed with the application of pressure. The application of pressure stabilizes the martensitic state and demonstrated that pressure can be a parameter used to control and tune the martensitic transition temperature (the temperature where the largest magnetocaloric effect is observed). The magnetic entropy change significantly decreases from 33 J/kg K to 16 J/kg K under the application of a hydrostatic pressure of 0.95 GPa. The critical field of the direct metamagnetic transition increases, whereas the initial susceptibility (dM/dH) in the low magnetic field region drastically decreases with increasing pressure. The relevant parameters that affect the magnetocaloric properties are discussed.

Highlights

The Mn-based Heusler alloys have been of considerable interest for several decades for their magnetic, half-metallic and many other interesting properties that have potential applications in microactuators, magnetic sensors, spintronics, and magnetic refrigeration.[1,2,3] They provide an excellent opportunity to vary the martensitic transition temperatures and magnetic states of austenitic and martensitic phases by changing the composition or doping with different 3d elements
The magnetic properties were measured at temperatures ranging from 5-400 K and in magnetic fields up to 5 T using a Quantum Design superconducting quantum interference device magnetometer (SQUID)
Ni45Mn43CrSn11 alloy is characterized by three phase transition temperatures: Curie temperature of martensitic phase (TCM), TM / TA, and Curie temperature of austenitic phase (TC), and shows a thermal hysteresis in the magnetization at TM

Summary

Introduction

The Mn-based Heusler alloys have been of considerable interest for several decades for their magnetic, half-metallic and many other interesting properties that have potential applications in microactuators, magnetic sensors, spintronics, and magnetic refrigeration.[1,2,3] They provide an excellent opportunity to vary the martensitic transition temperatures and magnetic states of austenitic and martensitic phases by changing the composition or doping with different 3d elements. Such variations strongly influence their properties, including normal and inverse magnetocaloric effects (MCEs), exchange bias, magnetoresistance, and Hall effects.[4,5,6,7,8]. A large magnetic entropy change and refrigeration capacity has been reported for Co and Si doped Ni-Mn-Sn Heusler alloys under the application of pressure.[12,13] Recently, we have studied the structural, magnetocaloric, thermomagnetic, and magnetoresistance properties of Ni-Mn-Cr-Sn Heusler alloys and observed large inverse magnetocaloric effects and giant magnetoresistance as a

Methods

Results

Conclusion