Reversible tensile strain dependence of the critical current in YBCO coated conductor tapes

摘要

The tensile strain dependence of the critical current, I-c, in two kinds of commercially available YBCO coated conductors (CC) and another one fabricated at KERI, which were processed by using the rolling-assisted biaxially textured substrates (RABiTS) and the ion-beam assisted deposition (IBAD) techniques, have been investigated. The mechanical properties including the Young's modulus and 0.2% offset yield stress at 77 K have been derived. The IBAD-processed samples showed a higher yield stress than the RABiTS/MOD processed one. Also, the irreversible strain/stress limits of I-c have been investigated at 77 K and self-field. The influence of stabilizer on the I-c degradation behavior in YBCO CC tapes with IBAD substrates was discussed. The irreversible strain limits defined by unloading could be explained well by the variation in the n-value-strain relation. (C) 2007 Elsevier B.V. All rights reserved.