Textured growth of multi-layered buffer layers on Ni tape by sol-gel process

Textured Cerium Oxide (CeO₂)/Yttrium-Stabilized Zirconia (YSZ)/CeO₂ buffer layers structure were grown by sol-gel dip coating process on bi-axially textured Ni tapes for processing of YBCO coated conductors. CeO₂/YSZ/CeO₂ buffer layer structure has been demonstrated by vacuum techniques, but first time textured CeO₂/YSZ/CeO₂ structure were grown by sol-gel on biaxially textured Ni tape. The buffer layer structure promoted c-axis oriented sol-gel YBCO films and prevented oxidation of nickel during YBCO processing. After each layer was coated, the layer was annealed. CeO₂ layers were annealed at 950 °C for 30 min. and YSZ layers were annealed at 1150 °C for 10 min. under 4% H₂ - Ar gas flow. Texture analysis of Ni substrates and bottom CeO₂ were done by Philips diffractometer. Sol-gel YBCO layers were coated on CeO₂/YSZ/CeO₂ structure and critical current density was about 0.5 × 10⁵ A/cm². Microstructure of the buffer layer was investigated by Environmental Scanning Electron Microscope (ESEM).