YbBaCuo钎料钎焊高温超导块材

Brazing of high temperature bulk superconductors with YbBaCuO solder

为了实现YBaCuO超导块材的大尺寸化,采用YbBaCuO钎料对YBaCuO高温超导块材进行了钎焊连接,分别测试了原始超导块材和钎焊接头的磁悬浮力,以评价钎焊接头的超导性能,并用SEM和能谱分析对钎焊接头的微观组织和成分进行了分析。磁悬浮力的测试结果表明,在本文工艺条件下,钎焊接头的磁悬浮力恢复比均可达原始块材的80%以上,甚至可达85.5%。SEM观察和能谱分析结果表明,在钎料和原始块材的界面之间,形成了一个明显的过渡层,过渡层的成分为(Y,Yb)混合相即(Y,Yb)-123相和(Y,Yb)-211相;在钎料的中部存在较多的小孔洞,是影响钎焊接头超导性能的主要因素。

The joining of high-temperature superconductor YBaCuO bulks was performed with YbBaCuO solder.The levitation force of the o- riginal bulk superconductors and the brazed joints was measured to evaluate the superconducting properties,and SEM and EDX was used to analyze the microstructure of the joints.The results demonstrate that the levitation force of the joints can reach up to 80% of the original YBaCuO bulks,even to 85.5%.The SEM and EDX analyses show that the transition layers are formed between the original bulks and the solder.The transition layers were comprised of (Y,Yb)123 phase and (Y,Yb)211 phase.The cavities in the solder and the transition layers were the key factor influencing the property of the joints.