MANUFACTURE OF A3B SUPERCONDUCTORS WITH BARRIER LAYER SYSTEM EMPLOYING METAL A

摘要

A superconductor of the general formula A3B, e.g. Nb3Sn, is manufactured by mechanical fabrication of A filaments in a bronze containing B followed by heat treatment to form A3B by solid state reaction from B diffusing through the bronze without melting of the bronze. A pure metal for stabilisation is mechanically fabricated together with the other components and protected from diffusion thereinto of any of the other components by a barrier layer of A metal. Superconductor formation on the harrier layer of A metal during the heat treatment is avoided or reduced by surface treatment or surface coating which inhibits A3 reaction between A and B at the barrier.