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Magnetic properties of the complex concentrated alloy system CoFeNi_0.5Cr_0.5Al_x.

ABSTRACT: We study the change in magnetisation with paramagnetic Al addition in the CoFeNi_0.5Cr_0.5-Al_x (x: 0, 0.5, 1, and 1.5) complex concentrated alloy. The compositions were developed utilising the Mulliken electronegativity and d-electron/atom ratio. Spherical FeCr rich nanoprecipitates are observed for X: 1.0 and 1.5 in an AlCoNi-rich matrix. A?~?5?×?increase in magnetisation (from 22 to 96 Am²/kg) coincides with this nanoprecipitate formation-the main magnetic contribution is determined to be from FeCr nanoprecipitates. The magnetisation increase is strange as paramagnetic Al addition dilutes the ferromagnetic Fe/Co/Ni additions. In this paper we discuss the magnetic and structural characterisation of the CoFeNi_0.5Cr_0.5-Al_x composition and attempt to relate it to the interfacial energy.

SUBMITTER: Morley NA

PROVIDER: S-EPMC7468281 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Magnetic properties of the complex concentrated alloy system CoFeNi0.5Cr0.5Alx.

Morley N A NA Lim B B Xi J J Quintana-Nedelcos A A Leong Z Z

Scientific reports 20200902 1

We study the change in magnetisation with paramagnetic Al addition in the CoFeNi0.5Cr0.5-Alx (x: 0, 0.5, 1, and 1.5) complex concentrated alloy. The compositions were developed utilising the Mulliken electronegativity and d-electron/atom ratio. Spherical FeCr rich nanoprecipitates are observed for X: 1.0 and 1.5 in an AlCoNi-rich matrix. A ~ 5 × increase in magnetisation (from 22 to 96 Am2/kg) coincides with this nanoprecipitate formation-the main magn ...[more]

PMID: 32879420

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