YbBa_2-xSr_xCu₃O_7-δ coated conductor development by sol-gel process

YbBa_2-xSr_xCu₃O_7-δ coated conductors were grown on Gd_1.8Ho_0.2O₃ buffer layered biaxially textured-Ni (100) substrates by the reel-to-reel sol-gel dip coating system. Sample with different Sr substitution ratio (x = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.6) were heat treated using varying heat treatment parameters. The surface morphologies and microstructure of all samples were investigated by ESEM, EDS and XRD. The critical current measurements were performed using four-wire method with the 1 μV/cm criterion. The critical current density, J_c was measured to be 10⁵ A/cm² at 4.2 K and 10⁴ A/cm² at 75 K in-self field for YbB _1.9Sr_0.1Cu₃O_7-δ sample.