Fabrication of YBa2Cu3O7-x (YBCO) superconductor bulk structures by extrusion freeforming

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 degrees C for 60 h, with the obtained constituent phases strongly dependent on the heat treatment temperature and duration. A high critical transition temperature (T-C=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. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.