Superconducting tube for shielding magnetic fields

A superconducting tube for shielding a magnetic field, comprising:

• a substrate comprising a tubular wall having radially inner and radially outer surfaces;
• an intermediate layer disposed radially inwardly of said substrate and comprising a noble material;
• a superconducting layer uniformly disposed radially inwardly of said intermediate layer, said superconducting layer consisting essentially of a superconducting oxide comprising a material selected from the group consisting of (i) a Bismuth compound containing Sr, Ca, Cu and O, and (ii) REBa.sub.2 Cu.sub.3 O.sub.7-y, wherein RE is at least one element selected from the group consisting of Y, Sm, Eu, Dy, Ho, Er and Yb, and y ranges from 0 to 1;
• and
• at least two ring-shaped reinforcing members welded to the radially outer surface of said tubular wall, each of said reinforcing members having a thickness of about 1 to 7 times a thickness of said tubular wall;
• wherein said intermediate layer prevents a reaction between said substrate and said superconducting layer.