Variation of the strain effect on the critical current due to external lamination in REBCO coated conductors

The effect of additional brass laminate on the strain tolerance of the critical current, Ic, in Cu-stabilized REBCO (RE standing for rare earth) coated conductor (CC) tapes was evaluated. The degradation behaviours of Ic under uniaxial tension at self-field and under a magnetic field, using a pair of permanent magnets, in REBCO CC tapes with different architectures, namely Cu-stabilized and externally laminated samples, have been investigated. The strain dependence of Ic in differently processed samples of SmBCO and YBCO CC tapes under uniaxial tension testing was measured at 0 T (self-field), 0.2 T, 0.3 T, and 0.5 T. The measured Ic/Ic0–eten relation for Cu-stabilized and externally laminated REBCO samples under a magnetic field showed that additional brass laminate enhances the irreversible strain limits from 0.5% to about 0.85% in REBCO CC tapes. The variation in the strain effect on Ic in brass laminated samples becomes minimal under a magnetic field in the range of 0–0.5 T for all REBCO CC tapes tested.