铁超导MgB2电线中的高临界电流
1Agere Systems/Lucent Technologies, Murray Hill, New Jersey 07974, USA. jin@agere.com
Nature
|June 1, 2001
概括
研究人员开发了一种新方法,可以制造密集的,金属覆盖的二氧化 (MgB2) 超导电线. 这些电线显示出高临界电流密度,为实用的散装超导体应用铺平了道路.
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:
- 大量超导体需要高临界电流密度 (Jc) 和保护性金属外.
- 二化物 (MgB2) 在39K时表现出超导性,为散装应用提供了潜力.
- 将MgB2制成实际的电线是具有挑战性的,因为它很脆弱,合成难.
研究的目的:
- 开发一种制造密集,金属的MgB2超导电线的方法.
- 为了证明这些制造的电线的运输临界电流密度 (Jc).
- 为了研究覆盖材料对MgB2超导性的影响.
主要方法:
- 铁MgB2电线的环境压力制造.
- 合成密集的MgB2与最小的损失的静脉测量.
- 在4.2K时测量运输临界电流密度 (Jc).
主要成果:
- 成功地制造出密集的,金属的MgB2超导电线.
- 在4.2K时实现了超过85,000Acm-2的运输Jc.
- 确定某些外材料显著降低了临界电流,表明污染诱导的弱环行为.
结论:
- 环境压力制造是生产高性能MgB2电线的有效方法.
- 选择覆盖材料对于保持MgB2的超导性能至关重要.
- 如果解决制造方面的挑战,MgB2电线对散装应用具有前景.
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