Oxidation of Ni and Ni-5% W


Oxidation of cube textured (100) 001 Ni and Ni-5%W foils were studied in order to verify ifNiO surfacelayer could be fonned on Ni-W similar to that Ni. The principle aim of this study is to prescribe the basic conditions forgrowing a compact, adherent, smooth, and cube texture NiO suitable to be used as a buffer layer in coated conductor,high temperature superconductor architecture. It was found that for Ni 30Jlm thick (002) NiO were fonned at oxidationtemperature of 1250 ± lOoe in air for 60 min. Under the same oxidation condition, (002) NiO with duplex-typemorphology was fonned on Ni-5%W which reduces the mechanical integrity of the sample. Furthennore, due to oxygendiffusion during the oxidation process, spherical NiW04 fonned inside the Ni-W substrate.Keywords: Oxidation, nickel, nickel oxide, nickel-tungsten, rolling assisted biaxially textured substratePACS: 74.72.Bk Y, 81.65.Mq. Z. Lockman\ M. H. Jamaluddin\ R. Nast2I School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia,14300 Nibong Tebal,Penang, Malaysia, 2Forschungszentrum Karlsruhe, Institut fur Technische Physik, Karlsruhe, Germany