Silver alloy sheathing material for ceramic superconducting wires

Abstract

The invention relates to a sheathing material for superconducting wires which are deformed during manufacture by drawing or a similar procedure. The superconducting material of the wires is composed of an oxide whose superconducting properties worsen during the deformation so that, in order to recover its original superconducting properties or to further improve them, the material must be subjected to a recovery heat treatment at temperatures above 940.degree. C. Customarily, silver is employed as the sheathing material for such wires. The recovery heat treatment is generally performed at temperatures around 900.degree. C. Experiments have shown that the optimum temperature range for a recovery heat treatment lies between about 940.degree. C. and 1030.degree. C. However, these temperatures were above the melting temperature of silver in an oxygen atmosphere. It is the object of the invention to find a sheathing material which has the favorable properties of silver but melts only at a temperature above the optimum temperature for the recovery heat treatment. This is accomplished according to the invention in that the sheathing material employed is a silver alloy whose melting point lies above the melting point of pure silver.

Dependencies are inferred from the claim text.