高エントロピーの磁石は,金属間化合物の独特の熱膨張を可能にします
Jinghan Li1, Kun Lin1, Hankun Xu1
1Beijing Advanced Innovation Center for Materials Genome Engineering, and Institute of Solid State Chemistry, University of Science and Technology Beijing, Beijing 100083, China.
Journal of the American Chemical Society
|October 24, 2024
まとめ
高エントロピー磁石 (HEM) を導入し 様々な磁気化合物を統合しました この新しいアプローチは,カゴメの金属間化合物の独特の磁気特性とほぼゼロの熱膨張をもたらします.
科学分野:
- 材料科学
- 凝縮物質物理学
- マグネティズム
背景:
- 高エントロピー戦略は,機能的な材料でますます使用されています.
- 高エントロピー磁石 (HEM) は,多様な磁気化合物を1つの相に統合します.
- HEMは独特の磁気特性を有することが予想されます.
研究 の 目的:
- 高エントロピー磁石 (HEM) の概念を紹介し,例示する.
- HEMの磁気および熱膨張特性を調査する.
- 新しい素材の機能性のためのHEMの潜在能力を探求する.
主な方法:
- 高エントロピー組成で合成されたAB2型層のカゴメインターメタル化合物.
- 温度に依存した測定を用いて磁気移行を調査した.
- 広い温度範囲で熱膨張の性質を分析した.
主要な成果:
- 競合する磁気状態と高エントロピーのサイト相互作用による複雑な磁気移行を観察した.
- 熱膨張の異常な変形 (正数,ゼロ,負数) を示した.
- 10〜360Kの (Ti1/5Zr1/5Hf1/5Nb1/5Fe1/5) Fe2で,ゼロに近い熱膨張 (αv = -0.62 × 10^-6 K^-1) を達成した.
結論:
- HEM戦略は複雑な磁気行動を持つ材料の作成を可能にします
- 磁気モメントのダイナミクスに関連した特定のHEM組成で,ほぼゼロの熱膨張が得られます.
- HEMは新しい機能的な固体材料を発見するための有望な経路を提供します.
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