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本文报道了超导材料的一种新合成方法——络合法。利用此法合成了名义组分为YB_(a2)Cu_3O_(7-δ)及单相的YB_(a2)Cu_3O_(7-δ)超导材料,分析了其最佳制备工艺(包括热处理温度、时间等)。并对样品进行了高温(20℃～1200℃)热分析研究,测定了样品中的氧缺陷。热分析研究表明:经络合加热脱水未经高温灼烧及热处理的样品,在冷却过程中,温度在788℃～652℃之间有一个二级相变,它是从有序的四方相——无序的正交相的结构相变。样品中的氧浓度随温度可逆的变化。经过反应及热处理的超导材料在加热过程中也表现出这种行为。这一结论对寻找这类新的高温超导材料的热处理工艺是很重要的。
This paper reports a new synthesis method of superconducting materials - complexation method. The YB_ (a2) Cu_3O_ (7-δ) superconducting materials with the nominal compositions of YB_ (a2) Cu_3O_ (7-δ) and single phases were synthesized by this method. The optimum preparation process, including the heat treatment temperature, Wait). The samples were subjected to high temperature (20 ℃ ~ 1200 ℃) thermal analysis, and the oxygen defects in the samples were measured. The results of thermal analysis show that there is a second-order phase transition from 788 ℃ to 652 ℃ during the cooling process in the samples that have not been heated and dehydrated by high-temperature heating and dehydration, Structural Phase Transitions of Disordered Orthogonal Phases. The oxygen concentration in the sample changes reversibly with temperature. After the reaction and heat treatment of superconducting materials in the heating process also showed this behavior. This conclusion is very important to find the heat treatment process of this new high temperature superconducting material.