Abstract. Chemical deposition methods like MOD and MOCVD are promising approaches for coated conductors (CCs) due to their reduced cost and easy scaling.High quality La2Zr2O7 (LZO) buffer layers were prepared by MOD on Ni-5%at.W (NiW) RABiTS and subsequent YBCO layers (450 to 800 nm thick) were deposited by pulsed injection MOCVD, leading to a simple low cost architecture NiWRABiTS/LZOMOD/YBCOMOCVD. In this novel combination of MOD and MOCVD approach, a single LZOMOD buffer layer is sufficient to ensure structural compatibility between YBCO and NiW, and protect the substrate from oxidation during YBCO MOCVD. YBCO films were epitaxially grown on LZO and exhibited critical current densities Jc close to 1 MA/cm2 at 77 K with a critical temperature Tc = 91 K and ∆Tc < 1 K.

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Bulk-textured YBa 2 Cu 3 O 7−x single domains could be used for current-limiting applications by cutting and assembling long meanders, which would be submitted to network electric fields before using a breaker to interrupt a fault current. For that purpose, large YBaCuO single domains up to 93 mm in diameter can be isothermally grown by using a standard melt texturing growth (MTG) process with a SmBaCuO seed. The essential parameters that have to be controlled in order to reach this size are the temperature growth window, the substrate reactivity and the temperature homogeneity in the sample. Standard 45 mm diameter single domains show excellent superconducting properties, such as J c above 10 5 A cm −2 and a homogeneous superconducting-to-normal transition at 91.8 K for 20 cm long conductors cut in these pellets. These measurements demonstrate the long -range homogeneity of single domains regarding T c and J c . Nevertheless the high J c values lead to a too large a dissipation in the normal state at T = 77 K. Different methods to reduce the critical current density are described in order to fulfill the conditions for a safe recovery of the material after undergoing a magnetothermal transition.

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