Practical neutral-axis conductor geometries for coated conductor composite wire

To optimize mechanical properties, particularly under bending deformation, a composite laminated architecture is proposed for second generation high temperature superconducting (HTS) coated conductor wire in which the superconductor layer is located at or near the neutral mechanical axis. 'Neutral-axis' conductors, each approximately 7 cm long, were fabricated by solder-laminating copper strip onto silver-coated HTS coated conductor strands. 'Neutral-axis' and non-laminated samples were bend/reverse-bend tested on mandrels of successively smaller diameters while measuring critical current after each reduction in mandrel size. The 'neutral-axis' samples showed significantly improved Ic retention compared to the non-laminated strands.