Study on Electromechanical Properties of Solder Jointed YBCO Coated Conductors With Etched Copper Stabilizer Under Axial Tension
The YBa<sub>2</sub>Cu<sub>3</sub>O<sub>7-x</sub> (YBCO) coated conductor (CC) is one of the most promising superconducting materials because of their high critical current (<italic>I</italic><sub>c</sub>) and low dependency of the <italic>I</italic><sub>c</sub> on the external magnetic field. For superconducting applications, a large number of joints are required to join relatively short YBCO CC tapes. In this paper, we study the electromechanical behavior of lap-jointed YBCO CC tapes fabricated by etching Cu stabilizer at its service temperatures (77 K) under self-field. The effects of etching Cu stabilizer on <italic>I</italic><sub>c</sub> and joint resistance (<italic>R</italic><sub>j</sub>) of YBCO CC tapes were discussed. The <italic>R</italic><sub>j</sub> was reduced and the <italic>I</italic><sub>c</sub> values of the joints are consistent with the parent CCs tape by etching the Cu stabilizer. Preferable electrical properties under applying axial tension are achieved and proved by the axial tension tests and finite element simulations. This fabrication technique is a unique practicable solution to reduce joint resistance for YBCO CC tapes with thicker metal stabilizing layers and improving electromechanical performance in second generation high temperature superconductor (2G HTS) devices.