Growth of Nd 2O 3 buffer layers on Ni tapes by reel-to-reel sol–gel process for YBCO coated conductors

Abstract

In this study, Nd 2O 3 buffer layers were deposited on textured Ni tapes using a reel-to-reel sol–gel process for YBa 2Cu 3O 7− x (YBCO) coated conductors. Depending on processing temperature, phase transformation in Nd 2O 3 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 30 s and then heat treated at 500 °C for 2 min 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 10–30 min 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 10 min under 4% H 2–Ar gas flow using modifying triethanol amin. ESEM images of Nd 2O 3 buffer layer showed crack-free, pinhole-free, dense and smooth microstructure.