  Nb-sheathed Sr0.6K0.4Fe2As2 superconducting wires have been fabricated using
the powder-in-tube (PIT) method for the first time and the superconducting
properties of the wires have been investigated. The transition temperature (Tc)
of the Sr0.6K0.4Fe2As2 wires is confirmed to be as high as 35.3 K. Most
importantly, Sr0.6K0.4Fe2As2 wires exhibit a very weak Jc-field dependence
behavior even the temperature is very close to Tc. The upper critical field
Hc2(0) value can exceed 140 T, surpassing those of MgB2 and all the low
temperature superconductors. Such high Hc2 and superior Jc-field performance
make the 122 phase SrKFeAs wire conductors a powerful competitor potentially
useful in very high field applications.
