Industrial Fe-Ni alloys for HTS coated conductor tapes

Best of the art of industrial rolling conditions have been developed to get a roughness inferior to 20 nm, improved further if necessary by electrolytic polishing (roughness of 6nm has been reached) or cold rolling. The effects of annealing conditions (temperature and atmosphere) on the cubique texture were analyzed. RX pole figures have been achieved on samples annealed up to 1100 deg. C. Attention has been paid to the rolling texture and to the annealing processes. The rolling texture has been found to be mainly copper-type (C, S and B contributions). Beginning of recrystallization occurred around 500 deg. C and stabilized between 1050 deg. C to 1100 deg. C, depending on the nickel content of the alloy, higher temperature annealing leading to overgrowth of grains. Finally, several samples, rolled and annealed under the appropriate conditions, have been characterized. Pole figure measurements gave the global in-plane and out-of-plane disorientations of our samples which are in-plane 5.5 deg. and out-plane (RD) 4.5 deg. for best samples. EBSD maps have shown the details of the distribution and show no twined {122}<21-2>orientations