由於超導塊材所能擄獲的磁場強度正比於其臨界電流密度(Jc)與單晶粒的尺寸大小。為提升其在工業應用的可能性，主要研究致力於如何提升其磁通釘扎能力(Flux pinning strength)以及成長更大此寸的單晶粒超導塊材。
本研究主要利用滲透法(Infiltration growth method)成長Y-Ba-Cu-O單晶粒超導體，並利用球磨與添加CeO2的方式，細化成長後Y-Ba-Cu-O單晶粒超導體內部Y2BaCuO5粒徑，藉以得到Jc的提升。
實驗結果顯示，利用滲透法成長的Y-Ba-Cu-O單晶粒超導體，其Jc比利用傳統頂端熔融製程方法成長(Top seed melt-texture growth)的Y-Ba-Cu-O單晶粒超導體高，且利用滲透法成長的Y-Ba-Cu-O單晶粒超導體沒有傳統頂端熔融製程的體積減縮問題，所以較易成長出較大的單晶粒超導體。
另一方面，利用球磨30分鐘細化Y2BaCuO5前驅物後，經滲透法成長的Y-Ba-Cu-O單晶粒超導體，其Jc稍稍比未球磨的提升一些；而利用添加1.5wt%的CeO2後，經滲透法成長的Y-Ba-Cu-O單晶粒超導體，其不論在低場或高場下的Jc皆有大幅的提升。

The magnitude of trapped field within bulk superconductors is proportional to the critical current density and the size of single grain. So, it is necessary to improve the flux pinning ability and produce larger size single grain RE-Ba-Cu-O, which are both key issues to practical applications.
In this study, we try to grow the Y-Ba-Cu-O single grain superconductors by the infiltration growth method (IG). The ball-milling technique and the doping CeO2 method are utilized to decrease the grain size of Y211 in the textured single grain YBCO superconductors and enhance the Jc.
The experimental results reveal that the Jc of the YBCO superconductor by the IG process is higher than that by the conventional top-seeded melt-textured growth method (TSMTG). And the outcome shows that the YBCO single grain produced by the IG process has no volume shrinkage problem. So, the YBCO superconductor could grow larger by the IG method.
In the other research, the Jc of the sample, which is after the 30 minutes ball milling decreasing Y211 precursors, increases a little bit by the IG process. And the doping CeO2 sample enhances the Jc drastic under the low and high applied magnetic field.

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