高温超导体散体磁铁,可以在29K处捕获超过17特斯拉的磁场
Masaru Tomita1, Masato Murakami
1Superconductivity Research Laboratory, Shibaura 1-16-25, Minato-ku, Tokyo 105-0023, Japan. tomita@rtri.or.jp
Nature
|January 31, 2003
概括
研究人员通过制造后处理增强了大量的--铜-氧化物 (Y-Ba-Cu-O) 超导体. 这提高了机械和热性能,使得创纪录的17.24 T磁场陷没有断裂.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 超导电性 超导电性 超导电性
背景情况:
- 大颗粒高温超导体 (RE-Ba-Cu-O) 适用于永久磁体应用,因为它们能够捕获显著的磁场.
- 目前的应用受到机械稳定性差和热导率低的限制,导致高磁压下的断裂.
- --铜-氧化物 (Y-Ba-Cu-O) 是这一类超导体中的一个关键材料.
研究的目的:
- 为了提高散装Y-Ba-Cu-O磁铁的机械性能和导热性.
- 为了提高这些超导体的磁场捕获能力.
- 为了克服阻碍超导磁体更广泛工程应用的局限性.
主要方法:
- 制造后处理包括树脂浸和碳纤维包装以提高机械性能.
- 用Bi-Pb-Sn-Cd合金灌中央孔,并加入一个线支.
- 这种双重方法旨在提高内部机械强度和热稳定性.
主要成果:
- 实现了热稳定性和内部机械强度的显著提高.
- 经过处理的散装Y-Ba-Cu-O磁铁显示了创纪录的17.24特斯拉 (T) 的被困磁场.
- 样本直径为2.65厘米,在29K时成功激活,没有断裂.
结论:
- 开发的后制造处理有效地提高了批量Y-Ba-Cu-O超导体的机械和热性能.
- 这一突破使得更高的磁场捕获能力成为可能,扩大了超导磁铁的潜在应用.
- 增强的稳定性和强度为更强大,更可靠的超导磁体技术铺平了道路.
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