Biaxially textured Ni-alloy tapes as substrates for buffer and YBCO film growth

Abstract Impurities in Ni processed by cold rolling and annealing for the purpose of producing a cube textured substrate for YBCO film deposition (RABiTS) often evoke secondary recrystallisation that destroys the cube texture at a temperature below the deposition temperature of the buffer. By adding small amounts of a second element the secondary recrystallisation can be suppressed and very strong cube textures with a FWHM below 10° and less than 1% highly misoriented grains are achieved. The suitability of such substrates is proved by superconducting films with a critical current density exceeding 0.5×10 6 A/cm 2 . The disadvantages of ferromagnetism and the low tensile strength of Ni as substrate material have been overcome by alloying with 13 at.% Cr or 9 at.% V. The yield strength of these well textured non-magnetic substrates is almost three times higher than that of Ni tapes.