The critical current of multifilamentary Nbhyphen;Hf/Cuhyphen;Snhyphen;Ga has been determined as a function of both field and strain at fields from 4 to 19 T. The strain dependence of the critical current is significantly reduced compared with that of commercial multifilamentary Nb3Sn superconductors. This reduced strain sensitivity, coupled with an enhanced criticalhyphen;current density above 12 T, make this a candidate material for economic highhyphen;field magnet construction. An analysis of the data in terms of the strain scaling law indicates that the Hf and Ga additives do not produce this improvement through a decrease in the strain sensitivity of the bulk upper critical fieldBast;c2. Rather, they reduce the strain sensitivity of the critical current through a changed shape of the flux pinning curve and an enhancement in the strainhyphen;free maximum value ofBast;c2(Bast;c2m= 25 T for Nbhyphen;Hf/Cuhyphen;Snhyphen;Ga versus 21 T for Nb3Sn).
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