Elongated grains in Ni5W(Ag) RABiTS tapes

Ni5W is a long known substrate material using the RABiTS approach. Elongated grains in the substrate tape would transfer to the superconductor epitaxially, where these are beneficial according to the brick wall model. 500ppm and 250ppm of silver were added to Ni5W and the intermediate and final heat treatments were altered from the standard process to obtain elongated grains. A maximum aspect ratio of 2.4 was realized in the alloy with 500ppm Ag.