Method for producing a superconductive fibre bundle

摘要

The invention relates to a method for producing a superconductive fibre bundle which consists of a multiplicity of supporting fibres, coated with a superconductive layer, such as carbon fibres, boron fibres and steel fibres. The superconductive layer in this case consists of fine-grained B1-structure niobiumoxycarbonitride having the general formula NbCxNyOz (x+y+z less than/equal to 1), whose mean grain size is between 3 and 50 nm. According to the method, a supporting fibre bundle is fanned out to form a supporting fibre strip. This is followed by the supporting fibres being coated on all sides with niobiumoxycarbonitride in amorphous form, by means of reactive cathode sputtering, a niobiumoxycarbonitride sintered target being used for precise metering of the non-metallic compound partners O2, N2 and C. Finally, in a subsequent heat treatment, the amorphous niobiumoxycarbonitride compound is converted into the fine-grained B1-structure. The reactive cathode sputtering can advantageously take place in a focusing magnetic field, which acts on the plasma density in such a manner that the electrons of the plasma are substantially kept away from the substrate. <IMAGE>