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本文采用X射线分析方法,研究了在不同淬火温度下YBa_2Cu_3O_7-δ超导材料的X射线衍射谱线和点阵常数的变化规律。发现在550℃以上温度淬火,YBa_2Cu_3O_7-δ超导材料,在液氮温区火去超导性能。在700℃以上温区淬火,出现BaCuOy非超导杂相。以Sr替代YBa_2CuO_7-δ相中的一部分Ba时,随Sr含量的增加,超导转变温度下降。X射线分析表明,这是由于氧在晶胞中的位置发生变化和微量失氧造成的。以稀土元素完全替代其中的Y,对结构和超导中点转变温度影响不大。
In this paper, X-ray analysis method was used to study the variation of X-ray diffraction lines and lattice constants of YBa 2 Cu 3 O 7-δ superconductors at different quenching temperatures. It was found that the superconducting YBa 2 Cu 3 O 7-δ material quenched at temperatures above 550 ℃ was de-superconducting in the liquid nitrogen temperature region. In the temperature above 700 ℃ quenching, there BaCuOy non-superconducting miscellaneous phase. When Sr is substituted for some Ba in YBa2CuO7-δ phase, the superconducting transition temperature decreases with the increase of Sr content. X-ray analysis shows that this is due to oxygen in the unit cell location changes and trace oxygen caused. Rare earth element completely replace the Y, the structure and superconducting midpoint transition temperature has little effect.