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Stabilisation of tetragonal FeCo structure with high magnetic anisotropy by the addition of V and N elements.

ABSTRACT: The development of magnetic materials with high saturation magnetization (Ms) and uniaxial magnetic anisotropy (Ku) is required for the realisation of high-performance permanent magnets capable of reducing the power consumption of motors and data storage devices. Although FeCo-based materials with the body-centred cubic structure (bcc) exhibit the highest Ms values among various transition metal alloys, their low Ku magnitudes makes them unsuitable for permanent magnets. Recent first-principles calculations and experimental studies revealed that the epitaxial FeCo thin films with the body-centred tetragonal (bct) structure and thicknesses of several nanometres exhibited Ku values of 106?J·m-3 due to epitaxial stress, which required further stabilisation. In this work, the FeCo lattice stabilised via VN addition were characterised by high Ku magnitudes exceeding 106?J·m-3. The obtained bct structure remained stable even for the films with thicknesses of 100?nm deposited on an amorphous substrate, suggesting its possible use in bulk systems.

SUBMITTER: Hasegawa T

PROVIDER: S-EPMC6437218 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Stabilisation of tetragonal FeCo structure with high magnetic anisotropy by the addition of V and N elements.

Hasegawa Takashi T Niibori Takuya T Takemasa Yusuke Y Oikawa Mitsuaki M

Scientific reports 20190327 1

The development of magnetic materials with high saturation magnetization (Ms) and uniaxial magnetic anisotropy (Ku) is required for the realisation of high-performance permanent magnets capable of reducing the power consumption of motors and data storage devices. Although FeCo-based materials with the body-centred cubic structure (bcc) exhibit the highest Ms values among various transition metal alloys, their low Ku magnitudes makes them unsuitable for ...[more]

PMID: 30918311

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Stabilisation of tetragonal FeCo structure with high magnetic anisotropy by the addition of V and N elements.

Publications

Stabilisation of tetragonal FeCo structure with high magnetic anisotropy by the addition of V and N elements.

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