원문정보
초록
영어
One of the major applications of REBCO coated conductor (CC) tapes is in superconducting magnets or coils that are designed for high magnet fields. For such applications, the CC tapes were exposed to a high level of stresses which includes uniaxial tensile or transverse compressive stresses resulting from a large magnetic field. Thus, CC tapes should endure such mechanical load or deformation that can influence their electromechanical performance during manufacturing, cool-down, and operation. It has been reported that the main cause of critical current (Ic) degradation in CC tapes utilized in coil windings for superconducting magnets was the delamination due to transversely applied stresses. In most high-magnetic-field applications, the operating limits of the CC tapes will likely be imposed by the electromechanical properties together with its Ic dependence on temperature and magnetic field. In this study, we examined the influence of the transverse compressive stress on the Ic degradation behaviors in various commercially available CC tapes which is important for magnet design Four differently processed REBCO CC tapes were adopted to examine their Ic degradation behaviors under transverse compression using an anvil test method and a newly developed instantaneous Ic measurement system. As a result, all REBCO CC tapes adopted showed robustness against transverse compressive stresses for REBCO coils, notably at transverse compressive stresses until 250 MPa. When the applied stress further increased, different Ic degradation behaviors were observed depending on the sample. Among them, the one that was fabricated by the IBAD/MOCVD process showed the highest compressive stress tolerance.
목차
1. INTRODUCTION
2. EXPERIMENTAL PROCEDURES
2.1. Samples
2.2. Anvil test method for the transverse compressive test at 77 K
2.3. Continuous Ic measurement system under transverse compression
3. RESULTS AND DISCUSSION
3.1. Electromechanical properties of REBCO CC tapes under transverse compression
3.2. Observations of damage in REBCO layer after transverse compression test
4. CONCLUSIONS
REFERENCES