1State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072 2National Engineering Laboratory for Superconducting Materials, Western Superconducting Technologies Co. Ltd., Xi'an 710018 3Superconducting Materials Center, Northwest Institute for Nonferrous Metal Research, Xi'an 710016
Abstract：Bi-2223 precursor powders are prepared by both oxalate co-precipitation (CP) and spray pyrolysis (SP) methods. The influence of fabrication methods on the superconducting properties of Bi-2223 tapes are systematically studied. Compared to the CP method, SP powder exhibits spherical particle before calcination and smaller particle size after calcinations with more uniform chemical composition, which leads to a lower reaction temperature during calcination process for Bi-2223 tapes. Meanwhile, the non-superconducting phases in SP powder are more uniformly distributed with smaller particle sizes. These features result in finer homogeneity of critical current in large-length of Bi-2223 tape, higher density of filaments and better texture after heat treatment. Therefore, the SP method could be considered as a better route to prepare precursor powder for large-length Bi-2223 tape fabrication.
2019, Vol. 36 
