Performance of a Copper-Clad Nb-40%Ti in a High-Current-Density 50-kG Superconducting Solenoid

Abstract

Coffey et al. [¹] reported the operation of a 100-kG superconducting solenoid using Nb-Zr and Nb-Ti superconducting wire. The Nb-Zr was used in the outer section of the coil, while Nb-Ti wire was used in the inside section. Since then, some of the attempts to use Nb-Ti wire have not been successful, The reason became apparent when it was discovered that Nb-Ti wire was supplied in a heat-treated condition with a thin copper coating. As with Nh-Zr, a heat treatment of the materials will increase the current carrying capacity, but at the same time will lead to instabilities which make them unsuitable for particular applications unless they are fully stabilized [²]. This paper reports on the stabilization of Nb-Ti superconducting wire, its heat treatment and its use in an operating coil.

Part of this work was reported at the American Physical Society Meeting, Jan. 1967.