Optimization of the properties of codoped single-domain Y–Ba–Cu–O bulk superconductors

The intrinsic effects of nanoscopic MnO2 powders addition combined with Fe cation substitutions for copper sites on the microstructure and superconductive properties of YBa2Cu3O7−δ (Y123) melt-solidified bulks have been investigated. On the one hand, an increase in Y2BaCuO5 (Y211) particle pushing, leading to an inhomogeneous bulk microstructure, is caused by increasing MnO2 content due to increased net interfacial energy, Δσ0; and, on the other hand, an addition of MnO2 powders is effective in enhancing both the δTc-type and δl-type pinning. It also shows that the Fe addition helps to optimize the high magnetic field performance and Y211 particle distribution in textured pellets. Further, this experiment suggests that a combination of the element substitution and the nanoscopic particle is a beneficial way to optimize the microstructure and superconductive properties of single-domain bulk superconductors.