Effects of liquid source mass and slow-cooling time on the infiltration growth of single-grain Y–Ba–Cu–O bulk superconductors

Abstract

The effects of liquid source (LS) mass and slow-cooling (SC) time on the infiltration growth of the YBCO single grains were investigated. Experimental observations indicated that, the growth rate of YBa2Cu3O7−x crystal increased with the increasing mass of the used LS pellet, and the optimal LS mass for IG process of Y2BaCuO5 preform bulk (12g) was identified as 20g. In addition, it was also found that the YBCO single grains grew much larger with the increasing SC time, and finally up to the whole sample size at a SC time 64h. A crooked a/c growth sector boundary was observed in the cross section of the YBCO single grain grown for 48h, which resulted from the variations of growth rate along different directions during the SC process. The results can help us develop more optimized IG process to fabricate YBCO single grains more economically and efficiently.