インタープラナー・フェロマグネティズム 強化超幅ゼロ熱膨張 カゴメ立方インターメタリック (Zr,Nb) Fe2
Yanming Sun1, Yili Cao1, Shixin Hu2
1Beijing Advanced Innovation Center for Materials Genome Engineering, Institute of Solid State Chemistry, Department of Physical Chemistry, University of Science and Technology Beijing, Beijing 100083, China.
Journal of the American Chemical Society
|July 25, 2023
まとめ
研究者は磁気ドーピングを使って 調節可能な熱膨張を持つ新しい立方金属を開発しました この材料は超広範囲の温度範囲でほぼゼロの熱膨張を示し,重要な技術的可能性を秘めています.
科学分野:
- 材料科学
- 凝縮物質物理学
- マグネティズム
背景:
- 熱膨張ゼロ (ZTE) 材料は先進技術にとって不可欠ですが,希少です.
- 金属の調節可能な熱膨張は,エンジニアリングのアプリケーションに非常に望ましい.
研究 の 目的:
- 調節可能な熱膨張を持つ新しい立方金属を合成し,特徴づけること.
- 金属材料の熱膨張をほぼゼロにするために,超広の温度窓を達成します.
主な方法:
- (Zr,Nb) Fe2インターメタル化合物の高温合成
- 熱膨張を調整するために鉄 (Fe) で磁気ドーピング.
- 分析のための磁気化,中性子粉の difraktion,およびMössbauerスペクトル.
主要な成果:
- 4Kから425Kまでの非常に同位型,ほぼゼロの熱膨張 (+0.47 × 10^-6 K^-1) を達成した.
- カゴメ立方 (Fd-3m) インターメタリックにおける磁気ドーピングによる調節可能な熱膨張が実証された.
- 格子収縮の磁気補償のメカニズムとして, インタープラナー・フェロマグネティック・オーダーリングを特定した.
結論:
- トレース・フェー・ドーピングはフェロ磁気と磁気調節温度を高め,超幅ZTEを可能にします.
- カゴメの金属材料は,ZTEの材料を開発するための有望なプラットフォームです.
- 開発された材料は,ZTEにとって,既存の多くの金属を上回る広い温度窓を示しています.
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