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High performance hot-deformed Nd-Fe-B magnets (Review)
1Corporate Research & Development Center, Daido Steel Co., Ltd., Nagoya, Japan.
Science and Technology of Advanced Materials
|February 8, 2021
Summary
Hot-deformed anisotropic Neodymium-Iron-Boron (Nd-Fe-B) magnets achieve higher coercivity by optimizing microstructure. This study enhanced production techniques, yielding heavy rare-earth-free magnets with 20% greater coercivity than conventional types.
Area of Science:
- Materials Science
- Solid State Physics
- Magnetism
Background:
- Hot-deformed anisotropic Nd-Fe-B magnets possess fine, oriented microstructures for high coercivity.
- Observed coercivity was limited to 25% of the anisotropy field potential, despite fine grain sizes near the single-domain critical diameter.
Purpose of the Study:
- Investigate the impact of chemical composition and hot-deformation conditions on Nd-Fe-B magnet properties.
- Identify optimal microstructural characteristics for enhanced magnetic performance.
- Improve hot-deformation techniques for better microstructure control.
Main Methods:
- Systematic variation of chemical composition and hot-deformation parameters.
- Microstructural analysis using advanced imaging techniques.
- Magnetic property characterization, focusing on coercivity.
Main Results:
- Established correlations between composition, deformation conditions, and microstructure.
- Optimized hot-deformation process based on experimental findings.
- Fabricated heavy rare-earth-free Nd-Fe-B magnets with coercivity > 1600 kA/m.
Conclusions:
- Microstructure optimization through controlled composition and hot deformation is key to high coercivity.
- Improved techniques led to significant coercivity enhancement in Nd-Fe-B magnets.
- Achieved superior performance in heavy rare-earth-free magnets, surpassing conventional types.
Keywords:
106 Metallic materialsHot-deformed Nd-Fe-B magnetcoercivityheavy-rear-earth-element freemicrostructureMore Related Videos
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