Study on Welded Joint Resistance and Mechanical Properties of REBa2Cu3O7−x Superconducting Tapes

In the process of preparing the high-temperature superconducting coil, the influence of the superconducting joint resistance and the mechanical deformation on the superconducting performance cannot be ignored. This article investigates the influence of different twisting angles, bending radii, and joint lengths on the critical current of the superconducting tape at 77 K. To control the experimental variables, both the twisting and bending experiments were performed with varying degrees of bending and torsion on the same superconducting tape. The experimental results show that the bending radius of the superconducting tape could not be less than 0.65 cm and the superconducting properties begin to decay at a twisting angle of 720°. In order to obtain the optimal welding length of superconducting joint, we prepared different lengths of joints with the same type of superconducting tape, and finally concluded that the resistance of superconducting joint when the welding length is 10 cm.