Fabrication of YBa2Cu3O7−x (YBCO) superconductor bulk structures by extrusion freeforming
Xiangxia Wei, Ragavendran Sundaram Nagarajan, Erwin Peng, Junmin Xue, John Wang, Jun Ding
Practical applications of high temperature superconductors may require them to be processed into complex geometries. In this work, slurry-based extrusion freeforming coupled with high temperature treatment was attempted for the fabrication of bulk YBa2Cu3O7−x (YBCO) superconducting structures. YBCO parts with approximately 93% of the theoretical density were successfully fabricated after sintering at 940 °C for 60 h, with the obtained constituent phases strongly dependent on the heat treatment temperature and duration. A high critical transition temperature (TC=92 K) and good magnetic levitation ability could be obtained after optimization of the heat treatment conditions. Overall, the experimental results demonstrate that extrusion freeforming is a feasible and effective technique for fabricating YBCO superconductors that have desirable configurations and good superconductivity properties.