The effect of Mn additions on the hysteresis loss and critical current density of power-metallurgy processed superconducting Nb/sub 3/Sn wires

摘要

Powder-metallurgy processed Nb/sub 3/Sn conductors were fabricated using a (Cu-1 or 3 wt.% Mn)-22.5 wt.%Nb composite. Plasma rotating electrode processed powders were used to improve workability. The Mn addition to the matrix increased the critical current density. The overall critical current density was about 1.5 approximately 2 times higher than that of conductors without Mn addition. It was found that Mn addition enhanced the reaction rate of Nb/sub 3/Sn through a catalysis-like effect of Mn. The Mn addition to the matrix decreased the hysteresis loss and the effective filament diameter. The lowest hysteresis loss was about 60% of the value of conductors without Mn addition. It was found that Mn addition depressed interfilamentary coupling.