Effect of metal composition ratios of solutions on Jc–B properties of REBCO coated conductors fabricated by advanced TFA-MOD process

Abstract

Metal organic deposition using trifluoroacetates (TFA-MOD) is expected as a low cost process of high Tc superconducting coated conductors, since this method does not need any high vacuum system. The advanced TFA-MOD process enabled us to produce YBa2Cu3O7−y (YBCO) films on IBAD buffered metallic substrates (PLD-CeO2/IBAD-GZO/Hastelloy) with high critical current density (Jc) values over 2MA/cm2 under the conditions of T=77K and the self fields.REBCO (RE:Y and Sm) films with different compositions were fabricated on the substrates by the advanced TFA-MOD process using TFA salts of Y, Sm, Ba and Cu-Naphthenate. The films which had excess amounts of (Sm), (Sm and Cu) or (Y and Cu) in addition to the stoichiometric 123 composition (Y:Ba:Cu=1:2:3) showed higher Jc values (>3MA/cm2) at 77K under the self fields compared with that of the stoichiometric composition film. In addition, the Jc values of the (Sm) or (Sm and Cu) added films were also improved under the high magnetic fields compared with that of the stoichiometric composition film. The origins of pinning centers were discussed from the perspectives of microstructures, crystal growth mechanisms, and so on.