High critical field superconductors and method for producing same

摘要

1028182 Super-conductor devices GENERAL ELECTRIC CO 30 Oct 1962 [2 Nov 1961 (2)] 41014/62 Headings H1A AS and A4D A super-conductor body comprises an electrically non-conductive base material associated with super-conductor material which provides a plurality of multiple connected current paths in the body whereby the super-conductor material can remain super-conductive in a magnetic field which exceeds that usual to the critical field for the material in bulk. In effect the super-conductor material becomes "harder." The base may consist of a porous ceramic, glass or plastics material such as alumina which provides a filamentary network. In one process, silica, boron oxide and a small amount of alumina are placed in dilute hydrochloric or sulphuric to leach out the boron oxide, the resulting filamentary network being filled by immersion in mercury which constitutes the superconductor; lead may be used in place of mercury and may be deposited on the walls only of the filamentary channels. In another example, the body comprises a hollow cylinder formed by a plurality of layers alternately of niobium and - silicon monoxide, or of tantalum and polyethylene. The super-conductor material may also consist of tin or aluminium.