Abstract
Ni and Ni-alloy substrates were used for the deposition of YBa/sub 2/Cu/sub 3/O/sub 7/-tape conductors. Cube texture of the metallic substrates was achieved by cold rolling and annealing at temperatures >850/spl deg/C resulting in well aligned cube texture. Tape samples up to 20 cm in length were heated up to the deposition temperature of 670/spl deg/C in a reducing Ar/H-gas ambient to remove oxides from the Ni substrate surface. Subsequently, CeO/sub 2/-based buffer layers were deposited by vacuum evaporation. YBa/sub 2/Cu/sub 3/O/sub 7/-films were grown on this tape by thermal co-evaporation and intermittent oxidation in a turntable substrate holder. We obtained transition temperatures up to 87 K and critical current densities at 77 K in excess of 1 MA/cm/sup 2/. Critical current characterization in external magnetic fields revealed an excellent power of resistance. Up to 10 T the critical current dropped only by a factor of two and leveled off at higher fields yielding 45 % of its zero field value even at 15 T.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.