The bending strain in the Nb
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Sn composite superconductors can cause degradation of the critical current in a significant portion of superconducting filaments. For a correct estimate of the bending strain in the "react and wind" coil conductors it is necessary to take into account that they can be deformed plastically during insulation and winding processes. Cases of plastic deformation due to the tensile stress in a macroscopically homogeneous multifilamentary composite superconductor the prestress of which is smaller than the yield stress in tension are considered in the paper.
