Stress/strain dependence of ac loss and critical current of Bi ₂Sr ₂Ca ₂Cu ₃O ₁₀ reinforced tape

The critical current and ac loss of a stainless steel reinforced Bi ₂Sr ₂Ca ₂Cu ₃O ₁₀ composite superconducting tape were measured under tensile stress/strain at 77 K. By use of the definition of irreversible strain, a formula describing the variation of the critical current with strain was proposed. A relationship between ac loss and tensile strain was developed from Norris' formula and the critical current-strain relation. It is shown that the experimental results agree well with the values calculated from our formulas.