SUPERCONDUCTING PROPERTIES OF CU-NB MULTI-FILAMENTARY COMPOSITE WIRESCONTAINING GA AS THE 3RD ELEMENT

Multi-filamentary superconducting wires of Cu70Nb30 and Cu70Nb29Ga1 ha ve been fabricated by an in situ technique. Doping Of Cu70Nb30 with Ga results in a small decrease in the transition temperature T(c). The c ritical current density J(c), however, increases appreciably. There is also a small increase in the upper critical field H(c2). The pinning force F(p) also increases on doping. The maximum (peak) value of F(p) is 1.79 x 10(4) N cm-2 for an undoped wire of diameter 0.20 mm and 3.1 8 x 10(4) N cm-2 for a doped wire of diameter 0.26 mm.