Growth of Nd₂O₃ buffer layers on Ni tapes by reel-to-reel sol-gel process for YBCO coated conductors

In this study, Nd₂O₃ buffer layers were deposited on textured Ni tapes using a reel-to-reel sol-gel process for YBa ₂Cu₃O_7-x (YBCO) coated conductors. Depending on processing temperature, phase transformation in Nd₂O₃ thin films was investigated. An Nd based precursor solution was prepared using solvent, chelating agents and modifying liquid material. The amorphous gel films were dried at 300 °C for 30s and then heat treated at 500 °C for 2min in air in the reel-to-reel sol-gel set up with three-zones furnace. The calcined films were annealed at temperature range of 850 and 1150 °C for 10-30min under two different atmospheres. It was found that cubic phase transformed to hexagonal structure up to 1000 °C. The textured films were grown onto the textured Ni tapes at 1150 °C for 10min under 4% H ₂-Ar gas flow using modifying triethanol amin. ESEM images of Nd ₂O₃ buffer layer showed crack-free, pinhole-free, dense and smooth microstructure.