Bi2223带材的临界电流及交流损耗研究

测量了77K温度下不同基体材料和不同芯数带材的临界电流和交流损耗.分析了弯曲应变对它们的影响.结果表明单芯样品的不可逆应变小于0.15%,而多芯样品的不可逆应变在01%到03%之间,多芯导体的机械性能比单芯导体的好,增加芯数可以提高机械性能,金属包套材料对超导芯起到了增强的作用,它防止了超导芯中裂纹的进一步传播.自场损耗随外加应变的增加而增加,这种大幅度的增加与应变使带材的临界电流急剧减小直接相关 关键词： 高温超导体 临界电流 交流损耗

The effects of bending strain on the critical current and alternating loss of Bi2223 HTS tapes

Self field losses in Bi2223 tapes with different base materials and different number of superconducting filaments were measured at 77K. And the influence of bending strain on critical currents and measured losses were analyzed. The results show that the irreversible strain for silver as the base material is less than 0.15%, and that of Bi2223/Ag Mn is more than 0.3%. The deterioration of the critical current due to the strain originates from the micro crack along the cross section of the superconducting core. Increasing the number of filaments and alloy base materials can improve its mechanical properties. The deterioration of critical current caused by bending strain leads to an increase in alternating losses.