Shell-ferromagnetism in Ni-Mn-based Heuslers in view of ductile Ni-Mn-Al

A Çakır,M Acet

doi:10.1063/1.4975792

Abstract

The present work deals with magnetic and structural phase instabilities in Ni-Mn-based Heusler alloys especially Ni-Mn-Al. The temper-annealed Ni50Mn45Al5 Heusler alloy decomposes into the full stoichiometric Ni2MnAl and NiMn phases. The decomposed stoichiometric Heusler forms precipitates in an anti-ferromagnetic NiMn matrix and exhibits shell-ferromagnetic properties when the temper-annealing is performed under magnetic field. The shell-ferromagnetism results from the magnetic proximity effect and is observed as vertically shifted magnetization loops. The presence of this property in Ni50Mn45Al5 adds the possibility of having a ductile material while preserving the shell-ferromagnetic properties.

Highlights

After their discovery in the beginning of the 20th century, Heusler alloys were intensively investigated because of their ferromagnetism, and later, at the turn of the 21st century, they reattracted interest because of their emerging multifunctional properties such as magnetic shape-memory (MSM), magneto-caloric effect (MCE), spintronic applications, and giant magneto-resistance (GMR).[1]
Ni-Mn-based type Heuslers with 3A-5A group elements Al, Ga, In, Sn, and Sb have been found to exhibit functionalities opening new application areas.[2,3,4]. The origin of these functionalities lie in the strong coupling between magnetic and structural degrees of freedom through the martensitic transitions and the accompanied large change of the magnetization
The magnetic and martensitic transition temperatures can be tailored by varying the composition choosing various combinations of the main group elements, thereby adjusting the temperature range of the functionality

Summary

Introduction

After their discovery in the beginning of the 20th century, Heusler alloys were intensively investigated because of their ferromagnetism, and later, at the turn of the 21st century, they reattracted interest because of their emerging multifunctional properties such as magnetic shape-memory (MSM), magneto-caloric effect (MCE), spintronic applications, and giant magneto-resistance (GMR).[1]. Shell-ferromagnetism in Ni-Mn-based Heuslers in view of ductile Ni-Mn-Al Acet2 1Metalurji ve Malzeme Muhendisligi Bolumu, Mugla Sıtkı Kocman Universitesi, 48000 Mugla, Turkey 2Faculty of Physics, Duisburg-Essen University, D-47048 Duisburg, Germany (Presented 1 November 2016; received 23 September 2016; accepted 11 November 2016; published online 6 February 2017)

Results

Conclusion