Stabilized high-field superconductor

• US 3,958,327 A
• Filed: 05/01/1974
• Issued: 05/25/1976
• Est. Priority Date: 05/01/1974
• Status: Expired due to Term

• Current Assignee: Airco, Inc.
• Original Assignee: Airco, Inc.
• Inventors: Marancik, William G., Ormand, Frederick T., Gregory, Eric
• Primary Examiner(s): Lanham, C. W.
• Assistant Examiner(s): Rising, V. K.
• Application Number:
  US05/465,970
• Time in Patent Office: 755 Days
• Field of Search: 29/599, 174/126 CP, 174/DIG. 6, 148/11.5 R, 148/127
• US Class Current: 29/599
• CPC Class Codes: H10N 60/20 Permanent superconducting devices
• CPC Class Codes: Y10S 505/92 Utilizing diffusion barrier
• CPC Class Codes: Y10T 29/49014 Superconductor
• CPC Class Codes: Y10T 428/12812 Diverse refractory group metal-base components: alternative to or next to each other

Abstract

A superconducting compound of the A-15 crystal structure type is obtained in a composite by a high temperature diffusion between a first metallic component and a second metallic component contained in a bronze alloy. Stability is achieved by including in the composite a quantity of high-conductivity normal material. Diffusion of the second metallic component into the normal material with a resultant degradation of conductivity of the normal material is prevented by placing an impervious barrier layer between the bronze alloy and the normal material. In a specific embodiment, the barrier layer takes the form of an annular shell comprising at least two sectors of dissimilar metals, one of which reacts with a component of the bronze alloy to form a layer of said superconducting compound, and the other of which is substantially non-reactive. Thus, a discontinuous superconducting ring is formed on the barrier layer which prevents flux trapping.

Claims

1. A stabilized high-field superconductor composite, comprising:

a bronze alloy matrix containing a plurality of parallel bores, wherein said alloy furnishes a metallic component of an A-15, Type II superconductive compound;

a plurality of metallic rods inserted into said bores, said rods being capable of reacting with said matrix during heat treatment at a predetermined reaction temperature to form said superconductive compound;

a sheath of normal material for stabilizing said composite surrounding said matrix; and

a barrier layer substantially impervious to diffusion by said alloy metallic component at temperatures up to and including said reaction temperature interposed between said normal material and said matrix, said barrier layer comprising at least two sectors wherein one said sector is essentially of metal selected from the group consisting of niobium and vanadium, and a second said sector is essentially of a dissimilar metal that does not substantially react with said matrix.

2. The combination in accordance with claim 1 wherein said dissimilar metal consists of molybdenum.

3. The combination in accordance with claim 1 wherein said dissimilar metal consists of tantalum.