Bi_2O_3掺杂对TSMTG法单畴YBCO超导块材性能的影响

The Effect of Bi_2O_3 Additions on the Properties of Single Domain YBCO Bulks by TSMTG process

本文采用顶部籽晶熔融织构法(TSMTG)成功地将Bi2O3掺杂到YBCO超导块材中,研究了Bi2O3掺杂含量对单畴YBCO超导块材生长形貌和磁悬浮力的影响.结果表明,在YBa2Cu3O7-δ(Y123):Y2BaCuO5(Y211)=1:0.4不变的情况下,掺杂的Bi2O3粉体在样品内部均生成了Y2Ba4CuBiOx纳米粒子.当Bi2O3添加量x≤1.5wt%时,样品均可长成完整的单畴YBCO超导块材,且样品的磁悬浮力随着Bi2O3掺杂量的增加而增大;当x>1.5wt%时,YBCO超导块材的单畴区域随着Bi2O3掺杂量的增加而逐渐减小,且随机成核现象严重,磁悬浮力降低;当x=1.5wt%时,样品的磁悬浮力最大.该结果对缩短样品制备的周期及进一步提高超导块材性能具有十分重要的意义.

The YBCO bulk superconductors with different Bi2O3 content have been successfully fabricated by the top-seeded melt texture growth process（TSMTG）,and the effect of Bi2O3 doping content on the magnetic levitation force is investigated based on the precursors of YBa2Cu3O7-δ：Y2BaCuO5=1：0.4.It is found that the Y2Ba4CuBiOxnano-particles can be formed with Bi2O3 doped.Completely single domain YBCO bulks have been synthesized when Bi2O3 doping content is less than 1.5wt%,The magnetic levitation force of the samples increase with the rising Bi2O3amount;When Bi2O3 addition is more than 1.5wt%,the single domain areas are small and random nucleations are more and more serious,so the magnetic levitation force is decreasing;The largest levitation force of the YBCO superconducting bulks can be obtained when Bi2O3 addition equal to 1.5wt%.The results are very important for further shortening the period of sample preparation and improving the properties of YBCO bulk superconductors.