Abstract: Superconducting fiber bundle which contains a multiplicity of carrier fibers such as, for instance, carbon fibers, boron fibers, steel fibers coated with a superconducting layer of a niobium compound of the general formula NbC.sub.x N.sub.y O.sub.z (x+y+z less than or equal to 1), characterized by the feature that the superconducting layer consists of fine-grained B1-structure niobium compound, the mean grain size of which is between 3 and 50 nm.

Abstract: Manufacture of superconducting fiber bundle coated with niobium carbonitride by a combination of the CVD process with a plasma activation under a low total gas pressure in which niobium chloride, carbon and nitrogen are reacted to produce the niobium compound which deposits from the gaseous phase on the carrier fiber to form a superconducting layer thereon. The combination of CVD process and plasma activation produces more uniform superconducting layers with smaller grain sizes. The application of an ultrasonic field may be combined with the CVD process. The superconducting layer consists of fine-grained B1-structure niobium compound, the mean grain size of which is between 3 and 50 nm.

Abstract: Superconducting fiber bundle which contains a multiplicity of carrier fibers such as, for instance, carbon fibers, boron fibers, steel fibers coated with a superconducting layer of a niobium compound of the general formula NbC.sub.x N.sub.y O.sub.