Y2BaCuO5粒子在准单畴超导块材中的分布及其对磁悬浮力的影响

熔融织构准单畴YBCO超导块材中的Y2 BaCuO5(Y-211)相粒子可以起到增强材料磁通钉扎力的作用.实验发现,顶部籽晶诱导生长熔融织构YBCO超导块材中的Y-211粒子分布呈不均匀性.Y-211相粒子在近籽晶处密度较低,而在样品底部则密度较高,并且呈现Y-211粒子团聚现象.通过优化Y-211相粒子在母体中的分布,可以有效提高YBCO块材的磁悬浮力.实验研究结果表明,Y-211相粒子在母体中的分布越均匀,且Y-211粒子平均粒径越小,则块材的磁悬浮力则越大.

DISTRIBUTION OF Y2BaCuO5 PARTICLES IN MELT-TEXTURED YBCO BULK SUPERCONDUCTOR AND ITS INFLUENCE ON THE LEVITATION FORCE

It is well known that Y-211 particles trapped in the melt-textured Y-123 superconductor can enhance flux pinning of the bulk. It was found that the Y-211 particle distribution within the bulk appears in an inhomogeneous character, which present a gradually changed Y-211 particle density from the upper zone near the top-seed, with little Y-211 particles, to the lower part near the bottom of the bulk with a marked Y-211 particles accumulation. The Y-211 inclusions, which is optimize artificially, in the meltedtextured YBCO bulk superconductor can enhance the levitation force of the bulk. Comparing the SEM analysis of the microstructure with the measuring of the levitation force show that the smaller the particle size and the more homogeneous the particle distribution is, the higher the value of the levitation force is presented.