Strengthening of biaxially textured Ni-alloys as substrates for YBCO tape conductors

Abstract Highly biaxially textured Ni tapes have been strengthened by introducing Al 2 O 3 particles with internal oxidation. The tape strength could be increased by a factor of five compared to pure Ni tapes. Therefrom an engineering current density increase by a factor of 4 can be derived by reducing the substrate thickness. Al-oxide formation at the surface of the tapes is prevented by the design of a composite tape consisting of an Al free surface region and an Al containing core with about the same strength. In this composite Al 2 O 3 only evolves in the tape core.