To increase the critical thickness of CeO2 single buffer layer, the polymer assisted chemical solution deposition (PACSD) approach has been adopted to prepare a single buffer layer of Gd0.3Ce0.7O1.85-x (GCO) on bi-axially textured Ni-5%W alloy substrate, and the influences of different annealing temperatures on texture and microstructure of the buffer layer has also been studied in this paper. The results demonstrate that a well textured, dense and smooth GCO single buffer layer with thickness of 180 nm has been obtained at 1100 ℃ annealing treatment. GdBa2Cu3O7-y (GBCO) film has been deposited on GCO buffered substrate via the similar approach, which is also well textured, dense and smooth. All these show that preparation of GCO buffer layer by PACSD method is an effective approach to prepare single buffer layer for large scale production.
Lei Ming1, Wu Wei1, Mu Liyun1, Zhao Yong1, 2 1 Key Laboratory of Magnetic Levitation and Maglev Trains (Ministry of Education of China), Southwest Jiaotong University, Chengdu 610031, China
A theoretical model of describing the electromagnetic and thermal dynamics of high-Tc superconducting bulks in a high-Tc superconducting Maglev system is built up.The model contains the effects of hysteresis-type loss,flux flow,flux creep,and thermal diffusion on the superconducting bulks in the Maglev system.As the first stage of this study,the behavior of magnetic and electric fields,as well as the distribution energy flow density in the superconducting bulk is studied.The results show that the flux flow and thermal diffusion affect the behaviors of the electromagnetic field in the high-Tc superconducting bulks in different ways;however,both of them contribute significantly to the energy dissipation of the superconducting bulks when they are used in the Maglev train.
YBa2Cu3O7-d(YBCO)-coated conductors have wide-ranging potential in large-scale applications such as superconducting maglev trains and superconducting electric cables, but low current carrying capability restrains the practical application of YBCO-coated conductors at high temperatures and high magnetic fields. It is crucial to develop YBCO-coated conductors with high critical current density. In this paper, epitaxial, dense, smooth, and crack-free Fe-doped YBCO films were prepared on a LaAlO3single crystal substrate via a fluorine-free polymerassisted metal organic deposition method. The effects of the dilute Fe doping on microstructure and superconducting character of YBCO films were investigated. The critical temperature for superconducting of the Fe-doped YBCO films decreases slightly. However, the in-field critical current density of YBCO films improves with dilute Fe doping of amounts less than x = 0.005, compared to the pure YBCO film. Therefore, the current carrying capability of YBCO film can improve by doping with appropriate amounts of Fe. This means that dilute Fe doping in YBCO films may be a feasible way to prepare high-performance coated conductors.
