YBCO coated conductor using biaxially textured clad composite Ni-Mn/Ni-Cr substrate

A new biaxially textured composite tape of Ni-4.5% Mn/Ni-1.5% Cr was used as a substrate for a YBCO coated conductor through the RABiTS approach. Multi-layer CeO₂/YSZ/Y₂O₃ buffer layers and YBCO film were deposited on the substrate by pulsed laser deposition. The deposition conditions of the buffer layers and the YBCO were studied and compared. Good biaxial textures have been obtained for buffer layers on composite Ni-4.5% Mn/Ni-1.5% Cr substrates. Scanning electron microscopy on sample cross-sections was used to examine the interface and diffusion of oxygen. The uniform formation of an Ni-Mn-O layer between NiO and the Ni-4.5% Mn layer was observed, and the Ni-Mn-O layer restricted the further growth of NiO layer, which was thin and not continuous, within the coated conductor during YBCO deposition at higher temperature and higher oxygen pressure. The J_c of YBCO films on these metal substrates was 1.5 × 10⁶ A cm ^-2 at 77 K, 0 T.