  We demonstrate a large enhancement of critical current density (Jc) up to
1.0x10^7 A/cm2 at 5 K under self-field in (Ba,K)Fe2As2 single crystals by
irradiating 320 MeV Au ions. With the very promising potential of this material
in mind, we have fabricated a (Ba,K)Fe2As2 superconducting wire through a
powder-in-tube method combined with the hot isostatic pressing technique, whose
effectiveness has been proven in industrial Bi2223 tapes. The Jc in the wire at
4.2 K has reached 37 kA/cm2 under self-field and 3.0 kA/cm2 at 90 kOe.
Magneto-optical imaging of the wire confirmed the large intergranular Jc in the
wire core.
