孔洞对Bi-2212超导圆线电磁特性及交流损耗影响研究
汪旭¹ 罗俊鑫¹ 张梁浩² 张红^{2（通讯作者）}

1西南交通大学物理科学与技术学院，四川成都，610031；

2西南交通大学电气工程学院，四川成都，611731；

摘要：在Bi-2212超导圆线的制备过程中，热处理工艺引发的内部气体释放往往会导致芯丝内出现不同程度的孔洞缺陷。这些孔洞不仅缩减了超导相的有效通流截面，更通过改变局部电磁场分布对线材的交流损耗特性产生复杂影响。本文基于三维有限元方法，采用Kim模型和幂律模型对Bi-2212超导圆线的交流损耗开展数值仿真研究。重点探究了孔洞尺度效应及径向分布不均匀性对传输损耗的影响机制。通过定量分析电流在超导域与银基质间的转移逻辑，旨在从微观缺陷视角揭示Bi-2212超导圆线在交变电流环境下的电磁特性及能量耗散演变规律，为优化高压热处理工艺以抑制损耗提供理论支撑。

关键词：Bi-2212超导圆线；孔洞；传输损耗；电磁特性

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