摘要 |
In the manufacture of a superconducting member fine filaments of niobium or vanadium in a bronze matrix are formed by mechanical reduction, e.g. by drawing, and by solid state reaction the filaments are converted to superconducting filaments of a compound of niobium or vanadium with, typically, one or more of the elements aluminium, gallium, indium, silicon, germanium and tin included in the bronze. Phosphorus is included in the bronze but care is taken to ensure that the bronze in contact with the filaments is free of unwanted impurities and in particular has a very low concentration of phosphorus, desirably in the range 0.01 to 0.05 percent by weight.
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