Degradation of Copper Stabilizer in a Superconducting Wire Induced by Cyclic Stressing at Cryogenic Temperature
For the long-term operation of high field pulsed superconducting magnet, increase in electrical resistivity of stabilizer in the superconducting wire is one of the significant damages resulted from repeated stress induced by its electro-magnetic force. Although efforts have been made to assess the degradation of this kind,1–3 some problems associated with experimental data covering the region of great many number of stress cycles still remain to be clarified. Resistivity change in copper during fatigue is somewhat complicated because of presence of many influencing factors such as stress/strain amplitude, purity of the test material and testing temperature.
KeywordsFatigue Recombination Helium Resis Perforation
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