室温轧制对Nb3(Al0.96Ge0.04)缺陷的调控及性能的研究
李文龙

西南交通大学物理科学与技术学院，四川省成都市，610031；

摘要：本文采用粉末装管法(PIT)制备了Nb3(Al0.96Ge0.04)前驱体圆线材并室温轧制成不同厚度的扁线材，通过减小线材尺寸来改变热处理过程中的传热条件。RHQ后，在Nb3(Al0.96Ge0.04)圆线中同时存在Nb(Al,Ge)ss和A15相。当线材厚度降低时，热量能够更快地传导与释放，这使得Nb(Al,Ge)过饱和固溶体更容易被保留下来。轧制后厚度为0.55 mm薄扁线在RHQ后，Nb3(Al0.96Ge0.04)得到了单一物相的Nb(Al,Ge)ss。在后续退火过程中，Nb(Al,Ge)ss向A15相转变时会产生大量可作为磁通钉扎中心的堆垛层错结构。厚度为1mm的Nb3(Al0.96Ge0.04)的扁线样品的临界电流密度相比于圆线提升了280%@4.2K,6T。通过厚度调控可促进Nb(Al,Ge)ss相的保留，退火后在样品中形成了更高密度的磁通钉扎中心。

关键词：Nb3(Al0.96Ge0.04)；室温轧制；堆垛层错

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