A textured Cu {100} 001 substrate for practical use in low cost coated conductor applications has been successfully fabricated. A textured Cu substrate is a promising substrate for a coated conductor template. This is the result of a low material cost base, no magnetization loss and good electro conductivity. One of the issues for a Cu substrate is surface oxidation. During REBCO deposition, the Cu substrate is exposed to an oxygen atmosphere, and de-lamination of the buffer layer can occur. To prevent this issue a thin Ni layer was formed on the textured Cu substrate by electroplating. After a further annealing process the Ni electroplated Cu substrates exhibit a good sharp texture and a smoother surface. The 1 and 1 of the substrate were about 4.6 and 4.5 degrees, respectively. The surface roughness was estimated at 6.8 nm Ra by AFM. Using this substrate and clad type Cu/SUS316 substrates, we deposited a CeO 2 YSZ CeO 2 layer by Pulsed Laser Deposition (PLD) and an YBa 2 Cu 3 O 7 layer by PLD and Metal-Organic Chemical Vapor Deposition (MOCVD). The results show no occurrence of de-lamination. Typical critical temperature of the coated conductors was 90.5 K and critical current density was a maximum of 4.5 MA cm 2 (at 77 K in a self-field).

We achieved a biaxially oriented YBa2Cu3O7 film on a {100} ⟨001⟩ textured Cu tape with Jc of 1.9×106 A cm−2 at 77 K. A Ni overlayer was deposited by electroplating technique on the {100} ⟨001⟩ textured Cu tape to improve oxidation resistance of Cu substrate, and then YBa2Cu3O7 was deposited on the CeO2/YSZ/CeO2 buffered Ni-electroplated Cu tape. We confirmed that the Ni-electroplated Cu tape lost its ferromagnetism after 700 °C at 1 h heat treatment. Our rolling assisted biaxially textured substrate (RABiTS) type coated conductor can be used for ac applications and is thought to be more cost feasible than the standard RABiTS architecture using Ni-alloy tapes.

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