Cu is an attractive metal to use as the sheath material for Sr1-xKxFe2As2 superconducting wires. However, unfavorable reactions between the Cu sheath and the superconducting core severely affect the superconducting performance. In this work, Cu-sheathed Sr1-xKxFe2As2 tapes are fabricated at a low temperature of 740 °C using a hot pressing method. A systematic correlation between the sintering holding time, reaction layer, microstructure, and superconducting properties is investigated. It is found that the samples that are hot pressed for 60 min exhibit the highest transport critical current density (J c), i.e. 3.5 × 104 A cm-2 in 10 T and 1.6 × 104 A cm-2 in 26 T at 4.2 K, respectively. Furthermore, the engineering critical current density (J e) value of the samples is over 1.0 × 104 A cm-2 in 10 T at 4.2 K. This is by far the highest J c reported for Cu-sheathed iron-based superconducting tapes.
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