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Development and characterization of cube-textured Ni–Cu–Co substrates for YBCO-coated conductors / A. Vannozzi in Acta materialia, Vol. 58 N° 3 (Fevrier 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 3 (Fevrier 2010) . - pp. 910–918 Titre : Development and characterization of cube-textured Ni–Cu–Co substrates for YBCO-coated conductors Type de document : texte imprimé Auteurs : A. Vannozzi, Auteur ; Gy Thalmaier, Auteur ; A. Angrisani Armenio, Auteur Année de publication : 2011 Article en page(s) : pp. 910–918 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : Nickel–copper  alloys  Thermomechanical  processing  Recrystallization  texture  Electron  backscattering  diffraction  Ceramic  superconductors Résumé : Ni–Cu–Co alloys were studied for the development of textured substrates for YBCO-coated conductor application. Three compositions were obtained by adding a fixed amount of 3 at.% Co to the binary NixCu100−x, where x = 40, 50 and 60. Cube texture was induced by conventional cold rolling followed by high-temperature annealing. The structural, microstructural, morphological, electrical, magnetic, mechanical and oxidation properties were evaluated and compared with those exhibited by the binary Ni–Cu alloy, as well as by Ni–W and pure Ni. A low Ni content is detrimental for the development of the cube texture with respect to higher concentrations. Nevertheless, the use of high annealing temperatures enabled an area fraction of cube orientation as high as 95% to be obtained for x = 40, and >97.5% in the case of Ni-richer alloys. Compared with Ni and Ni–W, Ni–Cu–Co alloys oxidize more easily and exhibit higher electrical resistance. In addition, the presence of copper enables the Curie temperature to be reduced to 60 K for x = 40 and to 155 K for x = 50. Furthermore, the introduction of cobalt reduces the oxidation rate at temperatures normally used for the deposition of ceramic buffer layers, thus allowing the successful development of a CeO2/YSZ/CeO2 architecture on ternary Ni–Cu–Co alloy. YBCO/buffer multilayer architecture deposited by pulsed laser deposition on a selected alloy tape exhibits a critical current density exceeding 1 MA cm−2 at 77 K in self-field, indicating that this alloy substrate is suitable for YBCO-coated conductor application. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409006855 [article] Development and characterization of cube-textured Ni–Cu–Co substrates for YBCO-coated conductors [texte imprimé] / A. Vannozzi, Auteur ; Gy Thalmaier, Auteur ; A. Angrisani Armenio, Auteur . - 2011 . - pp. 910–918. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 3 (Fevrier 2010) . - pp. 910–918 Mots-clés : Nickel–copper  alloys  Thermomechanical  processing  Recrystallization  texture  Electron  backscattering  diffraction  Ceramic  superconductors Résumé : Ni–Cu–Co alloys were studied for the development of textured substrates for YBCO-coated conductor application. Three compositions were obtained by adding a fixed amount of 3 at.% Co to the binary NixCu100−x, where x = 40, 50 and 60. Cube texture was induced by conventional cold rolling followed by high-temperature annealing. The structural, microstructural, morphological, electrical, magnetic, mechanical and oxidation properties were evaluated and compared with those exhibited by the binary Ni–Cu alloy, as well as by Ni–W and pure Ni. A low Ni content is detrimental for the development of the cube texture with respect to higher concentrations. Nevertheless, the use of high annealing temperatures enabled an area fraction of cube orientation as high as 95% to be obtained for x = 40, and >97.5% in the case of Ni-richer alloys. Compared with Ni and Ni–W, Ni–Cu–Co alloys oxidize more easily and exhibit higher electrical resistance. In addition, the presence of copper enables the Curie temperature to be reduced to 60 K for x = 40 and to 155 K for x = 50. Furthermore, the introduction of cobalt reduces the oxidation rate at temperatures normally used for the deposition of ceramic buffer layers, thus allowing the successful development of a CeO2/YSZ/CeO2 architecture on ternary Ni–Cu–Co alloy. YBCO/buffer multilayer architecture deposited by pulsed laser deposition on a selected alloy tape exhibits a critical current density exceeding 1 MA cm−2 at 77 K in self-field, indicating that this alloy substrate is suitable for YBCO-coated conductor application. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409006855