HIGH CRITICAL-CURRENT DENSITY SUPERCONDUCTING TAPES BY EPITAXIAL DEPOSITION OF YBA2CU3OX THICK-FILMS ON BIAXIALLY TEXTURED METALS

A method to obtain long lengths of flexible, biaxially oriented substr ates with smooth, chemically compatible surfaces for epitaxial growth of high-temperature superconductors is reported. The technique uses we ll established, industrially scalable, thermomechanical processes to i mpart a strong biaxial texture to a base metal. This is followed by va por deposition of epitaxial buffer layers (metal and/or ceramic) to yi eld chemically compatible surfaces. Epitaxial YBa2Cu3Ox films grown on such substrates have critical current densities exceeding 10(5) A/cm( 2) at 77 K in zero field and have field dependencies similar to epitax ial films on single crystal ceramic substrates. Deposited conductors m ade using this technique offer a potential route for the fabrication o f long lengths of high-J(c) wire capable of carrying high currents in high magnetic fields and at elevated temperatures. (C) 1996 American I nstitute of Physics.