High Current Density YBCO Coated Conductors On Strengthened Biaxially Textured Ni-W Substrates.

Paranthaman, M.

Technical Information Center Oak Ridge Tennessee

关键词: Yttrium oxides;    Barium oxides;    Copper oxides;    Substrates;    Current density;   

RP-ID  :  DE2001787478

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

High current density YBa(sub 2)Cu(sub 3)O(sub 7-(delta)) (YBCO) films were fabricated on rolling-assisted biaxially textured substrates (RABiTS) with a layer sequence of CeO(sub 2)/YSZ/(dip-coated or e-beam seed)/Ni-W (3 at. %). Electron-beam evaporation was used to deposit Y(sub 2)O(sub 3) seed layers. A reel-to-reel continuous dip-coating unit was used to deposit Gd(sub 2)O(sub 3) and La(sub 2)Zr(sub 2)O(sub 7) (LZO) seed layers. Scanning Auger Microprobe analysis of the textured Ni-W substrates indicated the presence of sulfur segregation at the surface. This possibly facilitated the growth of epitaxial e-beam Y(sub 2)O(sub 3) seed layers directly on Ni-W substrates through sulfur c2x2 superstructure. Highly aligned, continuous and crack-free Y(sub 2)O(sub 3), Gd(sub 2)O(sub 3), LZO seed layers were obtained. Both YSZ and CeO(sub 2) cap layers were deposited on all of these seed layers using rf-magnetron sputtering. The YBCO films were then grown on these buffered Ni-W substrates by either pulsed laser deposition (PLD) or ex-situ BaF(sub 2) precursor process. A high J(sub c) of 1.9 MA/cm(sub 2) at 77 K and self-field was obtained on both Y(sub 2)O(sub 3) and LZO seed layers. The performance of solution seed layers approached that of the vacuum seed layers.