A Novel Top‐Seeded Infiltration Growth Technique for Fabricating Y–Ba–Cu–O Single‐Grain Superconductor Nano‐Composites

Top‐seed infiltration and growth technique ( TSIG ) is proposed to fabricate Y–Ba–Cu–O ( YBCO ) single‐grain superconductor nano‐composites, in which a solid source composition of nano‐Y 2 O 3  + BaCuO 2 and a liquid source composition of Y 2 O 3  + 10BaO + 16CuO are employed. As can be seen, this novel technique uses just one source of precursor powder of BaCuO 2 , so it is more simplified and efficient. Microstructural observation indicates that fine Y 2 BaCuO 5 (Y‐211) inclusions with a size from dozens of nanometers to about one hundred nanometers are successfully introduced in YBa 2 Cu 3 O 7− x (Y‐123) superconducting matrix, which can act as more effective pinning centers for improving the bulk performance. Superconducting property measurement shows that, a maximum trapped field of 0.36044 T is present at the center of the sample after magnetization by a permanent magnet ( B  = 0.5 T). These results prove that our proposed TSIG technique is a practical method for fabricating YBCO bulk superconductor nano‐composites with high performance.