Flexible A-15 superconducting tape via the amorphous state

Abstract
The melt spinning technique was used to rapidly solidify superconducting materials. In the Ti3Nb6Mo3Si4 alloy system, it was possible to form metastable A‐15 and amorphous ribbons as the quenching rate was increased. The liquid‐quenched A‐15 ribbons were extremely brittle, which is typical of this crystal structure. The metastable A‐15 phase could also be formed by annealing the amorphous ribbons. These, however, were far more flexible, their percent elongation being up to 30 times greater than that of the liquid quenched A‐15’s. The flexibility appeared to depend on grain size, and increased as the grain size decreased. This is consistent with behavior observed in other brittle materials of a brittle to ductile transition as a function of grain size.