Improved V/sub 3/Ga for generating magnetic fields over 18 T

High field properties of surface diffusion processed (SDP) V/sub 3/Ga have been improved by a two-stage reaction process consisting of a reaction at a higher temperature to form a thick V/sub 3/Ga layer and a subsequent reaction at a lower temperature to achieve high T/sub c/ and H/sub c2/. Overall J/sub c/ at fields near H/sub c2/ depends mainly on the layer thickness and H/sub c2/ of V/sub 3/Ga. The two-stage reaction process has been found to appreciably improve the overall J/sub c/ of SDP V/sub 3/Ga at high magnetic fields. Overall J/sub c/ (including copper stabilizer) of 2 x 10/sup 4/ A/cm/sup 2/ at 19 T has been obtained by the two-stage reaction of the aluminum alloyed SDP V/sub 3/Ga. Using this improved SDP V/sub 3/Ga, a superconducting magnet generating a field of 18.1 T has been constructed