Dispersion strengthened and highly cube textured Ni alloy tapes as possible substrates for coated conductors Original Research Article

Ni and Ni base alloys are good candidate substrate materials in the development of long lengths of coated superconductors due to the development of strong cube texture following heavy cold working and recrystallisation. Increasing the tape strength is an important issue in order to facilitate the production of very thin and long lengths of high current carrying superconductors. The present paper reports the development of strongly cube textured and thin tapes (40 and 20 μm thickness) of an Ni–1 at.% Al alloy and strengthening of these tapes through controlled internal oxidation. Precipitation of finely dispersed Al2O3 particles increased the yield strength by a factor of 3–5 compared to pure Ni tapes without losing the strong cube texture. The problem of surface degradation due to precipitation of Al2O3 particles during internal oxidation was sought to overcome by the design of an Ni–Ni–1.5 at.% Al composite tape.