鉄板製の超伝導電線MgB2における高臨界電流は,
1Agere Systems/Lucent Technologies, Murray Hill, New Jersey 07974, USA. jin@agere.com
Nature
|June 1, 2001
まとめ
研究者らは,密度が高く,金属で覆われた二酸化マグネシウム (MgB2) の超伝導電線を製造する新しい方法を開発した. これらのワイヤは高い臨界電流密度を示し,実質的なバルク超伝導体アプリケーションの道を開く.
科学分野:
- マテリアルサイエンス 材料科学
- 凝縮物質物理学 凝縮物質物理学
- 超伝導性は超伝導性である.
背景:
- 大量超伝導体には,高い臨界電流密度 (Jc) と保護金属の覆いが必要である.
- マグネシウムジボリド (MgB2) は39Kで超伝導性を示し,大量の用途の可能性を秘めている.
- MgB2を実用的なワイヤーに製造することは,その脆さと合成の難しさのために困難です.
研究 の 目的:
- 密度が高く,金属で覆われたMgB2超伝導電線を製造する方法を開発する.
- これらの製造されたワイヤの輸送臨界電流密度 (Jc) を示すために.
- 覆面材料がMgB2の超伝導性に与える影響を調査する.
主な方法:
- 鉄板MgB2ワイヤの環境圧力製造.
- ステイキオメトリーの最小限の損失で密度の高いMgB2の合成.
- 4.2 Kで輸送の臨界電流密度 (Jc) を測定する.
主要な成果:
- 密度が高く,金属で覆われたMgB2超伝導電線を成功裏に製造しました.
- 輸送 Jc が 85,000 A cm-2 を超えて 4.2 K で達成しました.
- 特定の覆面材料が重要な電流を大幅に減少させ,汚染が誘発した弱いリンクの振る舞いを示すことを特定しました.
結論:
- 環境圧力製造は,高性能のMgB2ワイヤーを生産するのに有効です.
- コーディネート材料の選択は,MgB2の超伝導性を維持するために非常に重要です.
- MgB2ワイヤーは,製造上の課題を解決すれば,大量アプリケーションの有望性を示しています.
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