Intrinsic strain effect on critical current in Cu-stabilized GdBCO coated conductor tapes with different substrates

The intrinsic strain effect on critical current, I-c in Cu-stabilized GdBCO coated conductor (CC) tapes under bending and uniaxial tension has been investigated. The bending deformation tolerance of I-c in GdBCO CC tapes, fabricated by reactive co-evaporation by deposition and reaction (RCE-DR) with substrate materials of Hastelloy and stainless steel and fabricated by the metal organic chemical vapour deposition (MOCVD) process was evaluated. The intrinsic strain response of I-c under bending was found to be independent of the fabrication process, the substrate material and the geometry of the sample. For samples with a Hastelloy substrate, the intrinsic strain response of I-c/I-cmax under bending was well correlated with those under uniaxial tension. However, for samples with a stainless steel substrate, these had a large strain sensitivity for I-c under uniaxial tension even though this showed a much higher irreversible strain limit up to 1.05%.