Annealing-time and annealing-temperature dependencies of the size of Ni-Mn-In shell-ferromagnetic nano-precipitates by Scherrer analysis

L Dincklage,F Scheibel,M Farle,A Çakır,M Acet

doi:10.1063/1.5018851

Abstract

Shell-ferromagnetic effects are observed in Ni-Mn-based off-stoichiometric Heuslers decomposed into ferromagnetic precipitates embedded in an antiferromagnetic matrix when the surface-to-volume ratio of the precipitates are sufficiently large. However, since the size of the precipitates have until now not been determined, it is not known which ratios are involved. Here we carry out a Scherrer analysis on decomposed specimens to determine the precipitate-size as a function of decomposition temperature and time.

Highlights

Off-stoichiometric Ni-Mn-based Heuslers with composition Ni50Mn50xZx (Z: Al, Ga, In, Sn, Sb) are multifunctional materials undergoing magnetostructural martensitic transitions[1] and have potential applications in the areas of magnetic shape-memory,[2,3] magnetocalorics,[4,5] and giant magnetoresistance;[6] all in the room temperature range
There is one property of these off-stoichiometric alloys that has been largely overlooked when dealing with their multifunctionalities: These alloys decompose into cubic (L21) ferromagnetic (FM) Ni50Mn25Z25 and tetragonal (L10) antiferromagnetic (AF) Ni50Mn50 components when annealed in the temperature-range 600 ≤ T a ≤ 750 K.12–17
We carry out a Scherrer analysis on decomposed specimens to determine the precipitate-size as a function of decomposition temperature and time on Ni50Mn50xIn5 decomposed at various T a for various annealing times ta

Summary

Introduction

Off-stoichiometric Ni-Mn-based Heuslers with composition Ni50Mn50xZx (Z: Al, Ga, In, Sn, Sb) are multifunctional materials undergoing magnetostructural martensitic transitions[1] and have potential applications in the areas of magnetic shape-memory,[2,3] magnetocalorics,[4,5] and giant magnetoresistance;[6] all in the room temperature range. Annealing-time and annealing-temperature dependencies of the size of Ni-Mn-In shell-ferromagnetic nano-precipitates by Scherrer analysis

Results

Conclusion