Study of Growth Process for YBa2Cu3Oy Coated Conductors With BaZrO 3 Flux Pinning Centers by Monitoring Electrical Conductivity

Abstract

YBa 2 Cu 3 Oy (YBCO) coated conductors were prepared by a metal organic deposition method using a chemical solution with tri-fluoroacetate salts. A salt of Zr was also added into the solution to introduce BaZrO 3 (BZO) flux pinning centers into the YBCO films. The solution was coated on CeO 2 /LaMnO 3 /MgO/Gd 2 Zr 2 O 7 /Hastelloy substrates, and the coated films were crystallized at 1053 K. In this work, an additional holding temperature step was introduced during the crystallization of the films at 873 K to miniaturize the size of BZO nanoparticles, and then the effect of the heat treatment on the electrical conductivity of the film during the crystallization was examined. It was found that the conductivity of the film with the additional holding temperature step was approximately 1.7 times higher than that of the film fabricated without the one when the film temperature reached the crystallization temperature of 1053 K. In addition, the period until the conductivity saturated was three times smaller for the film fabricated with the additional holding temperature step. These results indicate that the growth temperature of YBCO shifts down and the holding period for YBCO crystallization can be shorter by introducing an additional holding temperature step.