Research on magnetomechanical optimization of superconducting joint for remctntable large SC magnet system

实验结果表明，对接方法的接触性能优于传统低温焊料连接方法中的研磨方法。Bi2223超导带（4mm × 0.3mm）在90%的临界电流下，接触电阻约为2微欧姆。这个值足够小，可以设计出可拆卸的超导磁体。如果采用单层叠层超导带，则电阻降至1微欧姆。然而，当传输电流超过90A时，电阻增加，而传输电流远小于层状超导带的临界电流。这可能是由于作用在截面上的压应力相对较小，实验外推结果需要约100Mpa才能达到理想的结果。数值计算结果表明，对接方法的性能不受各带中SC丝的相对位置的影响，这意味着对接方法在核聚变反应堆磁体中具有较大的可行性。

Experimental results show that the contacting performance of butt jointing method is better than that of lapping method used in traditional jointing method with low temperature solder. The contact resistance is about 2 micro ohm in case of Bi2223 superconducting tape (4mm x 0.3mm cross section) under 90% of its crilical surrent. This value is small enough to design the remountable superconducting magnets. In case of the flvelayer laminated superconductina tape, the resistance is reduced to 1 micro ohm. The resistance, however, increases when the transport current exceeds 90A, whose value is much less than the critical current of the laminated superconducting tape. This is maybe due to the relatively smallcornpressive stress acting on the cross section and experimental extrapolated results requires about 100Mpa to achieve the desirable results.The numerical results show that the performance does not deaend on relative location of SC filaments in each tape, which means that the butt jointing method has large feasibility for the magnet of fusion reactors.