超导股线Nb3Sn的性能测试研究

随着超导磁体的不断开发应用,对高临界电流密度超导材料的需求不断增长,以金属间化合物为基体的超导材料Nb3Sn具有特殊的实际意义,其制成的导体临界性能高于NbTi导体,Nb3Sn股线也是ITER磁体的关键组成部分.为了选择超导磁体合适的运行参数以及确定其稳定运行的范围,了解其超导特性是必要的.根据磁体设计所用标准,磁体运行时性能与股线的性能密切相关.本文介绍了一种测试Nb3Sn股线临界性能的方法,实验采用四引线法进行,测试中对样品提供了一个垂直方向的背景磁场,其大小可从0 T变化到16 T,实验时样品置于变温杜瓦内,温度调节通过控制进入变温杜瓦的氦气量来实现,可使温度变化小于0.01 K.对测试结果运用Summer定理进行了拟合并加以分析.

STUDY ON THE PERFORMANCE TEST OF SUPERCONDUCTING STRAND Nb3 Sn

The increasing need for high field magnetic devices has focused attention on filamentary Nb3Sn conductors, whose critical data are superior to NbTi conductors. To choose the suitable operating parameters and to determine the stability margin of magnet systems, it is very important to know the effect of temperature and magnetic field on the superconducting properties. The Nb3Sn strand is the key component of the ITER magnets. According to the design criteria, the performance of the coils in operation is strictly tied to the strand properties. This paper has shown an experimental method to measure the critical current of Nb3Sn strand. The background field is supplied by a magnet which is a high field superconducting magnet designed to produce fields up to 16 Tesla, and the direction of the magnetic field is vertical to the sample. We can control the temperature of strand by regulating the vacuum valve. And according to the result fitting used Summer law, it is shown that the method is useful for measuring.