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High transport currents in mechanically reinforced MgB2 wires

W. Goldacker·S. I. Schlachter·S. Zimmer·H. Reiner
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Abstract

We prepared and characterized monofilamentary MgB2 wires with a mechanically reinforced composite sheath of Ta(Nb)/Cu/steel, which leads to dense filaments and correspondingly high transport currents up to Jc = 10^5 A/cm^2 at 4.2 K, self field. The reproducibility of the measured transport currents was excellent and not depending on the wire diameter. Using different precursors, commercial reacted powder or an unreacted Mg/B powder mixture, a strong influence on the pinning behaviour and the irreversibility field was observed. The critical transport current density showed a nearly linear temperature dependency for all wires being still 52 kA/cm^2 at 20 K and 23 kA/cm^2 at 30 K. Detailed data for Jc(B,T) and Tc(B) were measured.

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W. Goldacker, S. I. Schlachter, S. Zimmer, H. Reiner. 2001-07-05. High transport currents in mechanically reinforced MgB2 wires. https://doi.org/10.1088/0953-2048%2F14%2F9%2F331

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