Vanadium-gallium

Vanadium-gallium (V₃Ga) a superconducting alloy of vanadium and gallium often used for the high field insert coils of superconducting electromagnets.

Vanadium-gallium tape is used in superconducting magnets (17.5 teslas or 175,000 gauss). The structure of the superconducting A15 phase of V₃Ga is similar to that of the more common Nb₃Sn and Nb₃Ti.

The high field characteristics can be improved by doping with high-Z elements such as Nb, Ta, Sn, Pt and Pb

Superconducting properties

• Critical temperature (T_c) : ~14.2 Kelvin
• Upper critical field (H_c2) : Over 19 Tesla.

Fabrication of superconductive wires or tapes

V3Ga wires can be formed using solid-state precipitation

• V3GaTape1.jpg

  V₃Ga superconducting tape (10×0.14 mm cross section). A vanadium core is covered with 15 µm V₃Ga layer, then 20 µm bronze (stabilizing layer) and 15 µm insulating layer. Critical current 180 A (19.2 tesla, 4.2 K), critical current density 20 kA/cm²

• V3GaWire.jpg

  An example of a wire (V₃Ga alloy) used in a superconducting magnet.