Uniform texture in meter-long YBa2Cu3O7 tape

A reel-to-reel tape handler mounted on a four-circle diffractometer is used to provide a characterization by X-ray diffraction of the entire 1 m length of a YBa2Cu3O7/CeO2/YxZr1-xO2/CeO2/Pd/Ni (YBCO/CeO2/YSZ/CeO2/Pd/Ni) tape. Cube-textured Ni was formed by rolling and annealing; epitaxial CeO2/YSZ/CeO2/Pd buffer layers were deposited by reactive sputtering; YBCO was converted ex situ from Y, BaF2, and Cu codeposited by e-beam evaporation. Rocking curve FWHM (mean +/- standard deviation) for 95 segments of 1 cm length are: YBCO(005) = 6.2 +/- 0.5degrees, YSZ(002) = 10.4 +/- 0.4degrees, and Ni(002) = 7.6 +/- 0.30. phi scan FWHM are: YBCO(113) = 9.6 +/- 0.4degrees, YSZ(111) = 13.0 +/- 0.4degrees, and Ni(111) = 10.6 +/- 0.4degrees. Greater than 95% of the tape at each point is cube textured from Ni to YBCO. The critical current density J(c) is 0.36 +/- 0.04 MA/cm(2) at 77 K and is inversely correlated with the rocking curve FWHM. Calculations suggest that J(c) might be increased by a factor of 2.1 by producing a sharper texture and that the uniformity of the texture will support scaling to kilometer lengths. (C) 2002 Elsevier Science B.V. All rights reserved.