Evaluation of Mechanical Property and Fatigue Damage in A Practical Superconducting Cable for Magnet

초전도 마그네트용 실용 초전도 복합선재의 기계적 특성 및 피로손상 평가에 관한 연구

  • Published : 2000.03.01


In order to investigate how the fatigue damage effects on the critical properties of superconductor, a fatigue test at room temperature and an Ic measurement test at 4.2K were carried out in this study, respectively, using a 9 strand Cu-Ni/NbTi/Cu composite cable. Through the fatigue test of a 9 strand Cu-NUNbTi/Cu composite cable, a conventional S-N curve was plotted even though there was a possibility of fretting among strands. It was found that the maximum stress corresponding to the inflection point on the S-N curve obtained was nearly the same value as the yielding strength of cable obtained from the static tensile test. However, the effect of cabling in multi-strands superconducting cable on the fatigue strength was not noticeable. The critical current(Ic) measurement was carried out at 4.2K in a NbTi strand out of the fatigued cable. It showed a degradation of lc at high stress amplitude regions over 380NTa, and the degradation became significant as the applied stress amplitude increased


Superconducting Cable;NbTi Composite Wire;Mechanical Property;S-N Curve;Fatigue Damage;Critical Current


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