Dense MgB2/Cu wires, with Ta as a buffer layer, were fabricated by using the powder-in-tube method. The microstructure was investigated by optical microscopy. Magnetization measurements were carried out by using a superconducting quantum interference device magnetometer at magnetic fields of up to 7T, from 5 to 35K. The transition temperature of the wire was about 38.4K and the irreversibility field was 6.6T at 5K. Critical current densities as high as 105A/cm2 (5K, self-field) and 104A/cm2 (20K, 1T) were obtained.

Fabrication and Superconducting Properties of MgB2 Composite Wires by the PIT Method. Y.Feng, Y.Zhao, A.K.Pradhan, L.Zhou, P.X.Zhang, X.H.Liu, P.Ji, S.J.Du, C.F.Liu, Y.Wu, N.Koshizuka: Superconductor Science and Technology, 2002, 15, 12-5