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REBCO coated conductor, the second-generation high-temperature superconducting (HTS) material, is one of the most promising materials for application in future fusion reactor high-field magnets due to its high critical current density and excellent mechanical properties. The Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP) is conducting the research and development activities on REBCO Twisted Stack Slotted-core Cables (TSSC) to validate the feasibility of CICC. In the manufacture and operation of high-field superconducting magnets, twisting, bending and transverse compression of cables are inevitable. Therefore, it is crucial to investigate the effect of mechanical properties on the electrical performance of TSSC cables. In this paper, an HTS TSSC cable based on vacuum soldering process has been developed and several measurements have been carried out at 77K and self-field. The effect of mechanical properties on the critical current (Ic) of TSSC cables was analyzed by means of experimental study and numerical simulation. Numerical simulations were able to calculate the Ic at different twist pitches and bending radii, and to predict the possible range in which the degradation of Ic occurred. The bending radii corresponding to the no-slip and perfect-slip models are approximately 1100 mm and 300 mm, respectively, when the criterion is taken to be 95% Ic retention. In the bending experimental tests, the samples to be tested were bent to a specified radius at room temperature, and then Ic measurements were taken at 77 K and self-field. A comparison of the performance changes of the cables under bending stress, both before and after vacuum soldering, was conducted to evaluate the effect of the soldering process on the bending performance. Furthermore, the compression experiments were performed by continuously applying progressively larger transverse loads to the samples in liquid nitrogen. In the monotonic transverse loading test, compression performance was better at 0° than at 45°, with Ic degradation to 95%, corresponding to a minimum load of 104 MPa. For cyclic transverse loading, there was no degradation in performance for 1000 cycles at 100 kN load, whereas at 120 kN load there was no degradation in performance for the first 10 cycles, with degradation to 91% and 73% after 50 and 900 cycles respectively. These results lay the foundation for large-scale applications of the REBCO CICC. The full-size CICCs with TSSC cables as sub-cables are being prepared for testing in the SULTAN facility to verify their operation stability under high electromagnetic loads for fusion applications.
