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Thick NiO films were grown in air, on biaxially textured (0 0 1) Ni and as-rolled Ni tapes, at temperatures from 1050 to 1350 °C. Ni diffusion through the NiO film mainly contributes to the growth since is much faster than oxygen diffusion and occurs by a vacancy diffusion mechanism in the lattice at high temperatures. Parabolic growth kinetics were found for both NiO film thickness and grain growth, and compared with the literature data. Competitive growth of (1 1 1) and (0 0 1) oriented grains establishes the final NiO orientation at temperatures below 1250 °C, while at higher temperatures leakage diffusion at/towards grain boundaries, grain coarsening and (1 1 0) oriented grains disrupt the (1 0 0) texture. Hence, development of epitaxy of NiO on textured Ni tapes was found to be largely due to growth kinetics depending on both, time and temperature. We report here a systematic study of the microstructure and kinetics of formation of textured NiO substrate for application as a buffer layer in coated conductor technology.

We report on the in situ growth and characterisation of c-axis oriented superconducting YBa2Cu3O7−δ/CeO2 structures deposited on biaxially textured Ni–Cr alloy tapes by respectively thermal and e-beam evaporation. We have studied the effect of growth temperature on the degree of texturing of both CeO2 and YBCO layers. We find that the highest degree of texture of both layers and best superconducting properties with sharp transitions and zero resistance Tc in excess of 85 K are obtained for substrate temperatures during deposition above 700 °C.

Pulsed laser deposition of different CeO 2 based buffer architectures have been performed onto biaxially textured Ni-based substrates. The potential of both industrially available low-oxygen resistant magnetic. NiFe and NiCrW substrates have been explored. An attempt to reveal the influence CeO 2 target doping and processing environment (vacuum or forming gas) on the formation of NiO as well as in-plane and out-of-plane orientation of the first buffer has been made. XRD has been used for layer texture characterisation. As-deposited YBCO layers were highly aligned on both types of substrate with out-of-plane and in-plane ω and ϕ scans having best FWHM values of 4° and 10° respectively. The quality of YBCO tapes as full-coated conductors or seeds for high-rate epitaxial growth by LPE is evaluated.

In recent years, world-wide research efforts have been made to develop YBCO coated conductors for high T c superconductor application in large scale devices. Since the demonstration of the rolling assisted biaxially textured substrates (RABiTS) route as a viable approach for the production of long HTS tapes, much work has been directed towards the development of new metallic substrates for high critical current densities coated conductors. The present work is focused in development of novel non-magnetic, high oxidation resistance, biaxially textured Ni based alloys. High purity Ni–Cr–W and Ni–Cr–V alloys were prepared by plasma arc furnace and the (0 0 1)[1 0 0] low thickness tapes were formed by recrystallization after heavy cold rolling. The microstructure of the tapes was investigated by θ –2 θ and pole figure X-ray analysis. The strength of the tapes was measured by stress–strain curves and thermogravimetric analyses were carried out to study oxidation properties of these alloys. The surface morphology of oxidised tapes has been studied by optical and SEM microscopy.