中文摘要：

采用顶部籽晶熔渗方法（TSIG）制备出直径为20mm的系列单畴YBCO块材，样品的成分为Y2Ba4CuZrOy（YZr2411）：（Y203＋1．2BaCuO2）=x：（1-x），其中，x=0、2、4、6、8、10，单位为wt％，并研究了不同掺杂量对块的表面形貌，磁悬浮力和微观结构的影响．结果表明，样品的表面形貌与YZr2411的掺杂量密切相关，当x≤2wt％时样品表面光滑且有明显的单畴性；当x≥4wt％时表面出现条形花纹．当32增大到8wt％以上时，样品就不能再保持原有的圆柱体形貌，而是向柱体外侧突出成四个扇瓣状．样品的磁悬浮力随着x增大先增大后减小，当x=6wt％时磁悬浮力最大为35．8N．样品显微结构表明，通过这种方法可以在YBCO超导块中引入纳米量级的YZr2411粒子，这些纳米粒子能够有效地提高YBCO超导材料的磁通钉扎能力．

英文摘要：

Single domain YBCO bulk superconductors, with diameter of 20mm and composition of Y2 Ba4 CuZrOs （YZr2411）： （Y2O＋1.2BaCuO2） =x： （1 -x）, wherein, x=0, 2, 4, 6, 8, 10, have been successfully fabricated by the top seeded infiltration method （TSIG）. The effect of YZr2411 additions on the surface morphology, magnetic levitation force and the microstructure has been investigated. The results show that the surface morphologies o{ the samples are closely related to the doping contentof YZr2411, the samples are of smooth surface and single domain morphology when x ≤ 2%, but the surface of the samples are of strip pattern shape when x ≥ 4 %furthermore, when x ≥ 8%, the sample can＇t keep the original cylinder shape, and result in four fan flaps protruding out of the original cylinder shape. The levitation force of the samples increases first and then decreases with the increasing of doping amount, the largest levitation force of up to 35N with x=6%. The microstructure of sample indicates that, nanometer YZr2411 particles can be well introduced into YBCO bulk superconductors, which can effectively improve the flux pinning capability of YBCO superconductor.